Question

Which one of the following conditions in humans is correctly matched with its chromosomal abnormality/linkage?

• A. erythroblastosis foetalis - X-linked
• B. Down's syndrome - 44 autosomes + XO
• C. Klinefelter's syndrome - 44 autosomes + XXY
• D. colour blindness - Y-linked.

Answer 1

Answer: (C)

Klinefelter's syndrome is a genetic disorder in which there are three sex chromosomes, XXY, rather than the normal XX or XY. The number of autosomes are normal i.e. Affected individuals are apparently male but are tall and thin, with small testes, failure of normal sperm production (azoospermia), enlargement of the breasts (gynaecomastia), and absence of facial and body hair.