Haemophilia affects males than females because of:
Correct answer: A. X linked recessive
- A. X linked recessive
- B. X linked dominant
- C. Dominant autosomes
- D. Y linked inheritance
Explanation
Haemophilia is an X-linked recessive disorder, which means it is more commonly seen in males than females. This is because the gene responsible for haemophilia is located on the X chromosome. Males have one X chromosome and one Y chromosome, while females have two X chromosomes. If a male inherits the faulty gene on his X chromosome, he will have haemophilia because he does not have another X chromosome to compensate for the faulty gene. Females, on the other hand, have two X chromosomes, so even if one X chromosome carries the faulty gene, the other X chromosome can often compensate for it. That's why haemophilia is more prevalent in males.
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About X-linked Recessive Inheritance
X-linked recessive inheritance involves genes on the X chromosome, so males express a recessive allele with no corresponding allele on their single X chromosome, while females may be carriers. Pedigrees cover haemophilia and red-green colour blindness, including carrier mothers, affected sons and the absence of father-to-son transmission.
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