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If I am blood type B, what are all the possible genotypes that could be expressed by my parents?
I think it might be 16 but I was reading online and saw this:
Similarly, someone who is blood type B could have a genotype of either BB or BO.
So if someone can help me answer this, that would be great.
Parent 1 and 2 have each 5 possible genotypes (OO, AO, BB, BO and AB).
Here a Punnett square with each possibilities. I highlighted the possible parent genotypes.
The total number of possible crosses is exactly 21. Note that here A = Ia, B = Ib and O = i.
This is starting from the information based on your blood type only (i.e. no information about your genotype).
Some background information. Antigen expressing alleles (here referred as Ia or A and Ib or B) are dominant. Not expressing an allele is notated i or O. Being of blood type O is when you don't express both alleles so it is a recessive trait (only possible genotype is ii or OO genotype).
21 crosses could be many more if you considered minor types as A2, A3, B3 or hybrid alleles as Ax, Bx or chimera AB alleles as cis-AB, B(A). These rare phenotypes break standard 4 type rules, for example, Ax/O genotype could be both type A or type O. It depends if you talk about genetcis or blood compatibility.
Understand the ABO, Rh and MN Blood Group Systems
Red blood cells have different antigens in the outer surface of their plasma membrane for example, the antigens A and B of the ABO system are glycoproteins of the membrane. If a donor has red blood cells with antigens not present in the red blood cells of the recipient (a lack of transfusion compatibility), the immune system of the recipient recognizes these molecules as actual antigens (or rather, foreign substances) and triggers a defense response, producing specific antibodies against those antigens. The transfused red blood cells are then destroyed by these antibodies and the recipient may even die.
The ABO Blood Group System
3. What are the antigens and the respective antibodies of the ABO blood group system?
The ABO blood system includes the erythrocytic antigens A and B that can be attacked by anti-A and anti-B antibodies.
A and B antigens are agglutinogens and anti-A and anti-B antibodies are agglutinins.
4. What are the blood types of the ABO blood system?
The blood types of the ABO blood system are type A, type B, the AB and type O.
5. What are the antigens and antibodies of each blood type of the ABO blood system?
Type A: Aਊntigen, anti-B antibody. Type B: B antigen, anti-A antibody. Type AB: A and B antigens, does not produce A or B antibodies. Type O: does not contain A or B antigen, has anti-A and anti-B antibodies.
(Obviously, antibodies are produced by B lymphocytes and not by red blood cells.)
6. What is the logic of the transfusion compatibility in the ABO blood group system?
The transfusion compatibility for the ABO system takes into account the antigens present in the red blood cells of the donor and the antibodies that the recipient can produce. Whenever the recipient is not able to produce antibodies against antigens of the red blood cells of the donor, the transfusion is compatible.
Therefore, regarding ABO compatibility, type A can donate to type A and to type AB. Type B can donate to type B and to type AB. Type AB can donate only to type AB. Type O can donate to all ABO types.
(Any transfusion must be studied, planned and supervised by doctors.)
7. What are universal donors and universal recipients in the ABO blood system?
Universals donors of the ABO blood type system are the individuals of the type O. Type O blood does not have A or B antigen in its red blood cells and can be donated to individuals of any ABO type.
Universal recipients of the ABO blood type system are the individuals of type AB. Type AB blood does not contain anti-A or anti-B antibodies and people of this group can receive blood from any of the ABO types.
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Genetics of the ABO Blood Group System
8. What type of genetic inheritance determines the ABO blood group system? What are the relations of dominance among the involved alleles?
The inheritance of the ABO blood system is a form of multiple alleles inheritance. There are three alleles involved, IA, IB and i which combine in pairs to form the genotypes.
Concerning dominance, the allele i is recessive in relation to the alleles IA and IB. Between IA and IB, however, a lack of dominance is established and the heterozygous pair (IAIB) has its own distinct phenotype.
9. What are the genotypes and respective blood types of the ABO system?
Since the alleles are IA, IB and i, the possible genotypes are IAIA or IAi (blood type A), IAIB (blood type AB), IBIB or IBi (blood type B) and ii (blood type O).
10. Is it possible investigate natural paternity, maternity or brotherhood and sisterhood using ABO blood typing?
By using ABO blood typing, it is only possible to exclude paternity, maternity or brotherhood/sisterhood. but it is not possible to come to positive conclusions about these relationships.
For example, if an individual has type O blood, ii genotype, he or she cannot have biological parents of the type AB (IAIB genotype), since one of his/her alleles has necessarilyome from the father and the other from the mother. Another example: a couple of individuals of the type O (ii) in turn can only generate direct offspring of type O blood, since they do not have alleles that condition antigen A nor antigen B.
The Rh Blood Group System
11. Is ABO blood compatibility enough for the safety of blood transfusion?
Besides ABO blood compatibility, the compatibility of the Rh blood system must also be checked. In addition, it is of fundamental importance for the safety of blood transfusion to perform tests to detect the agents of the main blood-transmitted infectious diseases, such as HIV (AIDS), hepatitis B and C, syphilis, Chagas disease, etc.
(Any transfusion must be studied, planned and supervised by doctors.)
12. What is the Rh factor?
The Rh factor is a protein in the red blood cell plasma membrane that behaves like an antigen in blood transfusions, triggering a humoral (antibody-based) immune response. Most people present the protein in their red blood cells and are part of the Rh+ group. People that do not have the protein classify as Rh-.
The origin of the name Rh factor is related to the fact that the research that discovered this blood antigen was carried out in rhesus monkeys (Macaca mulatta).
13. How are antibodies against the Rh factor formed?
Anti-Rh antibodies are produced by a humoral immune response. When an Rh- individual comes into contact with the Rh factor, it is recognized as foreign agent (antigen) the primary immune response begins and small amounts of anti-Rh antibodies and memory B lymphocytes are produced. In future contact with the antigen, antibodies will already be circulating, and memory immune cells will be prepared to carry out an intense and effective attack against the Rh factor.
14. What is blood typing?
Blood typing is the determination, by means of tests, of the classification of a blood sample in terms of blood group systems (especially the ABO system and the Rh system).
15. How is blood typing for the ABO system and the Rh usually done?
In blood typing for the ABO system and the Rh system, a blood sample is collected from the person and three small volumes of the sample are separated and dispersed on glass laminae (slides). On the first lamina, a serum containing anti-A antibody is applied on the second lamina, a serum containing anti-B antibody is applied on the third lamina, a serum with anti-RH antibody is applied. If no agglutination reaction takes place in any of the laminae, the blood is of type O- (universal donor) if agglutination occurs only in the first lamina the blood is type A- and so on.
There are other methods of blood typing. Blood typing must be performed by qualified technicians.
Genetics of the Rh Blood Group System
16. What are the inheritance and dominance patterns of the Rh blood system?
The inheritance pattern of the Rh blood system is autosomal dominant, meaning that the heterozygous individual is Rh+. The dominance is complete (R is dominant over r). The possible genotypes are RR, Rr (both Rh+) and rr (Rh-).
Interesting fact: the Rh factor is codified by a gene containing 2790 DNA nucleotides located on the human chromosome 1.
17. What is the logic of the transfusion compatibility concerning the Rh blood group system?
An Rh+ donor can only donate blood to an Rh+ recipient. A person that lacks the Rh factor (Rh-) can donate to individuals in both the Rh+ and Rh- groups.
Hemolytic Disease of the Newborn
18. What are the Rh groups of the mother and fetus in hemolytic disease of the newborn?
In hemolytic disease of the newborn, the mother is Rh- and the fetus Rh+. In this disease, antibodies produced by the mother attack fetal red blood cells.
Hemolytic disease of the newborn is also known as erythroblastosis fetalis.
19. How does the immune process that causes hemolytic disease of the newborn take place?
In hemolytic disease of the newborn, the mother has Rh- blood. This mother, when pregnant with first Rh+ child, comes into contact, possibly during delivery, with Rh+ red blood cells from the child and her immune system triggers the primary immune response against the Rh factor. In her next pregnanc, in which the fetus is Rh+, the mother will already have much more anti-Rh antibodies in her blod and these antibodies cross the placental barrier and enter fetal circulation, causing fetal hemolysis (destruction of the red blood cells of the fetus).
20. How can hemolytic disease of the newborn be prevented?
Erythroblastosis fetalis can be prevented if, during the first delivery of a Rh+ child from a Rh- mother, serum containing anti-Rh antibodies is given to the mother in the first 72 hours (after delivery). As result, the administered anti-Rh antibodies destroy the fetal red blood cells that entered the mother’s circulation before her primary immune response is triggered.
The MN Blood Group System
21. What is the MN blood system? What is the pattern of genetic inheritance of the MN blood system?
The MN blood system is a third (in addition to the ABO and the Rh) system of blood antigens, which is also related to proteins in the red blood cell plasma membrane.
The inheritance pattern of the MN blood system is autosomal with codominance, a type of lack of dominance in which the heterozygous individual manifests a phenotype totally distinct from that of the homozygous individual. The possible phenotypical forms are three blood types: type M blood, type N blood and type MN blood.
Understanding Blood Type Tests
The type A and type B carbohydrate molecules are called antigens because they can stimulate the body to produce an immune response, including antibodies. Each specific type of antibody binds to a specific antigen. For example, anti-B antibodies bind to type B antigens but not to type A antigens.
Normally, your body does not make antibodies against any antigens that are part of your body. For example, a person with type A blood
- Does not make anti-A antibodies against the type A antigen on his/her red blood cells
- Does make anti-B antibodies against the type B antigen which is not present on his/her red blood cells.
6. Fill in the blanks in this chart.
If you have type A blood, you have:
- Type A antigens on the surface of your red blood cells and
- ________ antibodies in your blood.
If you have type B blood, you have:
- Type B antigens on the surface of your red blood cells and
- ________ antibodies in your blood.
If you have type AB blood, you have:
Neither anti-A nor anti-B antibodies in your blood.
If you have type O blood, you have:
- Neither type of antigen on the surface of your red blood cells and
- Both ________ and ________ antibodies in your blood.
If you are given a blood transfusion that does not match your blood type, antibodies in your blood can react with the antigens on the donated red blood cells. This reaction can cause the donated red blood cells to burst and/or clump together and block blood vessels. A transfusion reaction can be fatal. To prevent this from happening, doctors test whether donated blood is compatible with a person&rsquos blood before they give a blood transfusion.
7. Explain how a type B blood transfusion could be fatal for a person with type A blood. Begin with the antibody-antigen reaction in a person with type A blood who has been given a type B blood transfusion. (Hint: See the figure at the top of the page.)
To test blood types, you will first mix a blood sample with a solution that contains anti-A antibodies. If the blood sample has type A antigens, they will react with the anti-A antibodies and this will result in clumping. Then, to test whether this blood has type B antigens, you will mix the second sample of this blood with a solution that contains anti-B antibodies.
8. To prepare to interpret the blood type tests, fill in the following chart.
|Blood Type||Will this blood type clump if mixed with|
|anti-A antibody||anti-B antibody|
Blood Type Problems
1. List all the possible genotypes for each of the 4 blood types:
Type O ____________ Type A ____________
Type B ____________ Type AB ____________
2. A man with AB blood is married to a woman with AB blood. What blood types will their children be and in what proportion?
3. A man who has type B blood (genotype: BB) is married to a woman with type O blood. What blood type will their children have?
4. A woman with type A blood (genotype: AO) is married to a type B person (genotype: BO). What blood types will their children have?
5. A woman with type A blood is claiming that a man with type AB blood is the father of her child, who is also type AB. Could this man be the father? Show the possible crosses remember the woman can have AO or AA genotypes.
6. A man with type AB blood is married to a woman with type O blood. They have two natural children, and one adopted child. The children's blood types are: A, B, and O. Which child was adopted?
7. A person with type A blood (unknown genotype) marries a person with type O blood. What blood types are possible among their children. (Show 2 crosses)
8. Two people, both with AB blood have four children. What blood types should the children be?
9. A person with type B blood (genotype BO) has children with a type AB person. What blood types are possible among their children?
10. A person with type O blood is married to a person with type A blood (unknown genotype). They have 6 children, 3 of them have type A blood, three of them have type O blood. What is the genotype of the two parents?
11. A person has type B blood. What are ALL the possible blood types of his parents. Show the crosses to prove your answer.
12. A man of unknown genotype has type B blood, his wife has type A blood (also unknown genotype). List ALL the blood types possible for their children. (you may need to do multiple crosses to consider the different possible genotypes of the parents)
13. Two people with type O blood have three children. How many of those three children also have type O blood?
14. Why is a person with type O blood called a "universal donor"?
15. Why is a person with type AB blood called a "universal acceptor"?
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Blood types are determined by the presence or absence of certain antigens – substances that can trigger an immune response if they are foreign to the body. Since some antigens can trigger a patient's immune system to attack the transfused blood, safe blood transfusions depend on careful blood typing and cross-matching. Do you know what blood type is safe for you if you need a transfusion?
There are four major blood groups determined by the presence or absence of two antigens – A and B – on the surface of red blood cells. In addition to the A and B antigens, there is a protein called the Rh factor, which can be either present (+) or absent (–), creating the 8 most common blood types (A+, A-, B+, B-, O+, O-, AB+, AB-).
Blood Types and Transfusion
There are very specific ways in which blood types must be matched for a safe transfusion. The right blood transfusion can mean the difference between life and death.
Every 2 seconds someone in the US needs a blood transfusion.
Use the interactive graphic below to learn more about matching blood types for transfusions.
Also, Rh-negative blood is given to Rh-negative patients, and Rh-positive or Rh-negative blood may be given to Rh-positive patients. The rules for plasma are the reverse.
- The universal red cell donor has Type O negative blood.
- The universal plasma donor has Type AB blood.
There are more than 600 other known antigens, the presence or absence of which creates "rare blood types." Certain blood types are unique to specific ethnic or racial groups. That’s why an African-American blood donation may be the best hope for the needs of patients with sickle cell disease, many of whom are of African descent. Learn about blood and diversity.
What Is A Universal Blood Donor?
Universal donors are those with an O negative blood type. Why? O negative blood can be used in transfusions for any blood type.
Type O is routinely in short supply and in high demand by hospitals – both because it is the most common blood type and because type O negative blood is the universal blood type needed for emergency transfusions and for immune deficient infants.
Approximately 45 percent of Caucasians are type O (positive or negative), but 51 percent of African-Americans and 57 percent of Hispanics are type O. Minority and diverse populations, therefore, play a critical role in meeting the constant need for blood.
Types O negative and O positive are in high demand. Only 7% of the population are O negative. However, the need for O negative blood is the highest because it is used most often during emergencies. The need for O+ is high because it is the most frequently occurring blood type (37% of the population).
The universal red cell donor has Type O negative blood. The universal plasma donor has Type AB blood. For more about plasma donation, visit the plasma donation facts.
If someone has blood type A+: which are his possible genotypes and who can he donate blood to?
The ABO blood type system relies upon the co-dominant alleles I A and I B , which are expressed any time they are present and are dominant over i which is recessive. If someone has blood type A, that means in their genotype they have at least one I A allele, for otherwise they would not express phenotype A. In addition we can infer, they do not have allele I B in their genotype, because if they had it, they would express it. So the possible genotypes of someone whose phenotype is A+ are: I A I A (homozygote: both alleles are the same) and I A i (heterozygote: alleles are different). In both cases , A would be expressed and B would not, so the phenotype would be A. Regarding the +/- blood type, this trait is determined by the presence of the allele Rh which is dominant over rh (which is recessive). Whenever Rh is present, it is expressed and the phenotype is +. Since for the studied individual the phenotype is +, we know Rh is present. But we do not know if the individual is heterozygote or homozygote: so there are two possible genotypes RhRh and Rhrh.
Regarding blood donation, the key idea to consider is that one can only donate to people that have the same antigens (traits like +, A or B) than one has. This includes people who have the same antigens plus some extra ones. The reason for this is that the body only rejects antigens that are foreign to theirs. An individual with phenotype A+ has got antigens A and +. So he cannot donate to people who do not have antigens A and +: that rules out A- (they do not have +), B- (they do not have A or +), AB- (they do not have +), 0- (they do not have A or +), 0+ (they do not have A) and B+ (they do not have A). So the studied individual can donate to: A+ (share A and + and have no extra antigen) and AB+ (they share A and + and have the extra antigen B)
Possible genotypes for blood types? - Biology
BLOOD TYPING LAB REPORT (Upload this report by Tuesday 5/12 at 11:59pm).
Watch the two Blood typing videos in the YouTube Blood Typing playlist I linked to your google class page. The first video gives you the genetic theory of blood types and blood donation. The second video shows you the results of an actual blood typing activity. You will be answering the questions below based on information from the first video and experimental results from the second video.
Let’s assume the people whose blood types were assessed in the second video are real people. The woman Mary is the mother of a girl whose name is Clarissa. Clarissa is sick with blood cancer and needs blood transfusions and tissue donations from a compatible healthy donor. Clarissa’s blood type is O positive.
Unfortunately Mary isn’t completely sure who Clarissa’s father is. It could be any one of the three men whose blood types were tested in the second video: Chris, Mike or Bob.
Clarissa’s doctor wants to test the blood types of Mary, and all three men who might be Clarissa’s dad, to try to find who would be the best match for Clarissa for blood transfusion and tissue donation.
For this report you will need to use the blood typing results for Mary, Chris, Bob, and Mike presented in the second video to fill out the results chart below, and then answer the four additional questions about the results below the chart.
WHO IS CLARISSA’S FATHER? BLOOD TYPING RESULTS CHART
Blood Type (Both ABO and Rh type, from the results presented in the second lab video)
Possible ABO genotypes for this person (From the information presented in your information sheet)
Possible Rh genotypes for this person (From the information presented in your information sheet)
Possible genotypes for blood types? - Biology
Human Blood Type Sample Problems
Table 1: The following tables give information on human blood types needed in problems below. Alleles of types I A and I B are dominant over type i.
1. A patient is rushed to the emergency room and has suffered severe blood loss. Type AB blood is in short supply, but the nurse says "Don't worry, he's type AB positive. We can give him any kind of blood." Explain. (Why is type AB called the universal recipient?)
A person who is AB positive has every kind of protein in his blood. There is nothing in any blood type that would be "foreign" to his body, so rejection is not a problem.
2. On the battlefield, a medic is treating a soldier who has lost a great deal of blood. They are out of blood typing supplies so the medic, who is Type O negative, simply donates his own blood to the patient. Why could this work? (Why is Type O called the universal donor?)
A type O negative person has none of the proteins that can cause rejection in his blood, so his blood can be accepted by anyone.
3. There is a practical joker in the maternity ward who removed all the baby id bracelets. There are three babies that cannot be easily distinguished and the parents want to be sure they get the right ones back so the doctors do a blood test. A particular mom is homozygous type A and the dad is type O. The babies have blood types AB, A, and O. Show your work below and indicate which baby must be theirs.
4. The police have rounded up the usual suspects in the latest rash of bookstore robberies. The thief got a nasty paper cut at the scene of the crime. The suspects are of blood types O, A, B and AB. The blood at the crime scene contained i alleles. Which suspect therefore cannot have been involved? Explain.
Release Suspect #4 because his blood contains no i alleles.
5. In a paternity case, a single mother claimed that a certain man was the father of her baby. The man denied it, claiming that her current boyfriend was the father. The court ordered a blood test (much cheaper than DNA testing) to see if he could be ruled out as the father. The mother was Type O and the baby was Type O. The man was Type AB. Is it possible that he was the father? Why or why not?
The man's genotype is IAIB and the mother's ii. The baby's genotype is also ii. This makes it impossible for the man with type AB blood to be the father of this child.
6. Why is it that a blood type test can only disprove but never prove paternity? Why are DNA tests used to "prove" paternity instead?
A baby can, in some circumstances, have a blood type that could not possibly be produced by a mating of two particular individuals, as shown in the example above. This would be sufficient to disprove paternity. However, there are only a handful of blood types, and many people have them, so while there are cases where a man of a certain blood type could be the father of a child, so could anyone else with that same blood type. DNA tests can be used more effectively to "prove" paternity, because the possibility of a child having a close DNA match to a non-relative is extremely rare. However, a good lawyer knows that nothing in science can be proven absolutely. Samples sometimes do get contaminated and chance events, though rare, do sometimes happen. The lottery odds may be one in a million, but that's different from zero.
7. (True Story) In Denmark, a husband and wife who had been unsuccessfully trying to have a baby went to a fertility clinic. Sperm and eggs were collected from father and mother, and combined in a petri dish, creating several "test-tube babies". These babies were implanted in the mother and 9 months later she delivered twins, one with light skin and one with dark skin. Because this seemed strange, a DNA test was conducted and it was found that both children were related to the mother, but only the light skinned child was related to the father. How can this be explained?
Infidelity seems unlikely because of the timing of conception she would have to have slept with another man at very close to the same time that she was implanted with her husband's sperm at the fertility clinic. A more likely explanation is that a test tube or dropper was accidentally used repeatedly without being sterilized, causing sample cross-contamination. DNA tests in this case did reveal that the father of the second child was another client of the fertility clinic who had never met the mother.
8. Rh factors are proteins that were first discovered in the blood of Rh esus Monkeys, but humans have them too. If you are Rh positive, it means that there are Rh type proteins in your blood. If you are Rh negative, there are no Rh type proteins in your blood. Positive is dominant over negative, so heterozygous individuals are Rh positive. Problems can arise when an Rh negative mother has a child who is Rh positive. Why does the mother's body attack her own baby in this situation? Why does the situation get worse for the second pregnancy?
The mother's body sees the foreign proteins produced by her baby as a threat. She builds up antibodies against them. The baby is delivered before the situation gets too out of hand, but the next pregnancy will be more problematic because her immune system is sensitized and fully prepared at the onset of the next pregnancy. Her immune system attacks the baby, often resulting in a miscarriage. Immune suppressing drugs can be given to the mom, but then she's more likely to get sick because her body's germ fighting ability is diminished.
9. The father of two children is type O+, and the mother is type A+. The children are O- and A+. Given this information, what can you say about the genotypes of father and mother?
If the father is O+, his ABO genotype is ii, and he may be either Rh +/+ or +/-. If the mother is Type A+, her ABO genotype is either IAIA or IAi and her Rh type is either +/+ or +/-.
However, if either of the children is Rh-, then both of the parents must be Rh +/- because, in order to get a -/- child, each parent must have had one -.
If one of the children is type O, then the mother must have been IAi, because otherwise the child could only be type A.
So, the father is ABO genotype ii, Rh type +/-, and the mother is ABO genotype IAi and Rh type +/-.
Possible genotypes for blood types? - Biology
I have heard that certain combinations of blood types in parents cannot possibly give rise to particular blood types in their offspring - indeed, several plays and stories have used this as a plot device to reveal at some point that a person's social father could not have been his/her biological father. Is this true, or a myth? And if true, what are the "impossible" combinations?
- You can have any combination of A and B - i.e. you can have A (just A), B (just B), AB (both) or O (neither), and you can pass either of these "letters" on to your children. But you can't pass on a letter you haven't got, so if I'm AB and my mum is B then my dad must be either A or AB - because otherwise where would my A come from?
A is dominant to O
B is dominant to O
A&B are co-dominant
You get one gene, A, B, or O, from your father and one from your mother. What you get from each is your genotype, what is expressed in your blood is your phenotype. The possible genotypes for an individual are (the order is not really relevant):
AA: Phenotype - A
BB: Phenotype - B
OO: Phenotype - O
AO: Phenotype - A
BO: Phenotype - B
AB: Phenotype - AB
So two pure breeding individuals of A B or O can only give rise to A B or O children. However, using normal blood tests it is impossible to tell the genotype of an individual who has an A or B blood group.
Hence a person with one parent with A blood group and one person with B blood group with genotype AO & BO can produce children of any blood group, so nothing can be proved. If a person of O blood group breeds with a person of B group all the children must be either B or O. If the child is A or AB one of the individuals cannot be the parent. An O and B crossing can not produce an A or AB child. An AB with an O can produce A children or B children but not O.
In short the ABO system can prove you are not a parent but not that you are, as there are millions of other people with the same blood group.
Clotting, Depression, and Allergies
While many of the genes that we retain for generations are either beneficial or neutral, there are some that have become deleterious in our new, modern lives. There are several genes that our Neanderthal relatives have contributed to our genome that were once beneficial in the past but can now cause health-related problems (Simonti et al 2016). One of these genes allows our blood to coagulate, or clot, quickly, a useful adaptation in creatures who were often injured while hunting. However, in modern people who live longer lives, this same trait of quick-clotting blood can cause harmful blood clots to form in the body later in life. Researchers found another gene that can cause depression and other neurological disorders and is triggered by disturbances in circadian rhythms. Since it is unlikely that Neanderthals experienced such disturbances to their natural sleep cycles, they may never have expressed this gene, but in modern humans who can control our climate and for whom our lifestyle often disrupts our circadian rhythms, this gene is expressed more frequently.