求一道数学概率题Men have XY or (YX) chromosomes and women have XXchr

首页/题库/410℃/2024-05-09 17:32:12

求一道数学概率题

Men have XY or (YX) chromosomes and women have XXchromosomes. X-linked recessive genetic diseases (such as juvenileretinoschisis) occur when there is a defective X chromosomes thatoccurs without a paired X chromosome that is good. In thefollowing, represent a defective X chromosome with lower case x, soa child with the xY or Yx pair of chromosomes will have thedisease, while a child with XX or XY or YX or xX or Xx will nothave the disease. Each parent contributes one of the chromosomes tothe child.

a. If a father has the defective x chromosome and the mother hasgood XX chromosomes, what is the probability that a son willinherit the disease?

b. If a father has the defective x chromosome and the mother asgood XX chromosomes, what is the probability that a daughter willinherit the disease?

优质解答：

a) A son's X(or x) must be inherited from his mom,he must have XY or YX,the probability is 0,impossible.

b) A daughter must have Xx or xX in this case,the probability is also 0.

I'm not gonna translate the whole piece.Since I could read through and understand it,translating is just wasting my time.Sorry.

Feel free to ask if you have any question or concern.

再问： If a father has the defective XY chromosome and the mother has good Xx chromosomes, what is the probability that a son willinherit the disease? :)

再答： 1/2

Because The X (or x) must be inherited from mother.

Therefore xY and XY have equal chance to occur in the next generation.

我来回答修改/报错/举报内容！

猜你喜欢