If neither parent has haemophilia and the child has X-linked haemophilia and turner syndrome, then the nondisjunction event in which parent caused the turner syndrome in the child? Also, is the nondisjunction in meiosis I or II ? Could you explain?
I understand that the child inherited the recessive X- allele (which caused haemophilia) from the mother. Does it mean that nondisjunction occured in the mother?
I understand that the child inherited the recessive X- allele (which caused haemophilia) from the mother. Does it mean that nondisjunction occured in the mother?
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no, since the father is not affected by haemophilia that means the lone X chromosome came from the mom.
since father did not give any X to child, that means, there was disjunction with the dad's meiosis.
Turner is an example of monosomy. So, it must have happened in meiosis 1, because if non-disjunction in meiosis 1, there will be no normal gametes produced after meiosis 2.
just for shetz and giggles, if there was nondisjunction in meiosis 2, then there would be 2 normal gamete, 1 gamete with 2 chromosomes, and 1 gamete with no chromosome. this does not cause monosomy.
Turner only affect females, so there is no sense of saying child. just say its the daughter
since father did not give any X to child, that means, there was disjunction with the dad's meiosis.
Turner is an example of monosomy. So, it must have happened in meiosis 1, because if non-disjunction in meiosis 1, there will be no normal gametes produced after meiosis 2.
just for shetz and giggles, if there was nondisjunction in meiosis 2, then there would be 2 normal gamete, 1 gamete with 2 chromosomes, and 1 gamete with no chromosome. this does not cause monosomy.
Turner only affect females, so there is no sense of saying child. just say its the daughter
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yes, non-disjunction in meiosis 1 for the father. Think about it. You got your X and Y sex chromosomes. If there was non-disjunction, you will have the X and Y chromosomes in the same cell and the other cell with no X and Y. Then after meiosis 2, the sister chromatids of the mismatched in 2 gametes
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and the other 2 gametes will have no X or Y chromsome. There is no way in hell you can get a monosomy from this shet. Turner syndrome is a monosomy. So the daughter has mom's x. also, since the dad doesn't have hemophilia, the X cant be from the dad.
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I'm sorry, I meant , yeah, meiosis 1 is it..hehe, i'm getting confused
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I mean, if there is non disjunction in meiosis 1, then the half of your 4 gametes will be abnormal and the other half are nullisomy. Nullisomy offsprings usually die early in term and the the abnormal gametes can't cause monosomy. Turner is monosomy.
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