A normal girl, whose mother is haemophilic, m | vedclass

Name: Exam Paper Generator | JEE NEET Paper Generator | Vedclass
Brand: Vedclass
Rating: 5 (35 reviews)

Question

(B) Haemophilia is an $X$-linked recessive disorder.Let $X^H$ be the normal allele and $X^h$ be the haemophilic allele.The mother of the girl is haemo

Vedclass · Accepted Answer

$(b)$ and $(c)$ only

Vedclass · Answer

(B) Haemophilia is an $X$-linked recessive disorder.Let $X^H$ be the normal allele and $X^h$ be the haemophilic allele.The mother of the girl is haemophilic, so her genotype is $X^h X^h$. She must pass one $X^h$ chromosome to her daughter. Since the girl is normal, her genotype must be $X^H X^h$ (carrier).The male has no ancestral history of haemophilia, so his genotype is $X^H Y$.Cross: $X^H X^h$ (carrier female) $	imes$ $X^H Y$ (normal male).Offspring genotypes: $X^H X^H$ (normal daughter), $X^H X^h$ (carrier daughter), $X^H Y$ (normal son), $X^h Y$ (haemophilic son).Possible phenotypes: Normal daughter, carrier daughter, normal son, and haemophilic son.Thus, the possible phenotypes include normal daughter, normal son, carrier daughter, and haemophilic son. Options $(b)$ and $(c)$ correctly describe these possibilities.

Similar Questions

Which of the following diseases results from the genetic inability to synthesize a single enzyme?

$A$ husband and wife have normal vision,but the fathers of both of them were colour blind. What is the probability of their first daughter being colour blind (in $\%$)?

$A$ colour-blind man marries the daughter of a colour-blind person. Then in their progeny:

The gene for colour blindness is carried by:

Study the given pedigree chart and select the correct option for the given questions.
$(1)$ Is the trait recessive or dominant?
$(2)$ Is the trait sex-linked or autosomal?

Vedclass Test Series

Exam Paper Generator

Online Exam Module