Which of the following disorders are the results of aneuploidy?
(A) Haemophilia
(B) Down’s Syndrome
(C) Thalassemia
(D) Turner’s Syndrome
Choose the correct answer from the options given below:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → (B) and (D) only
(A) Haemophilia — Incorrect. It is a sex-linked recessive Mendelian disorder, caused by a change in a single gene for a blood-clotting protein. The chromosome number stays normal.
(B) Down’s Syndrome — Correct. It is trisomy of chromosome 21, so the person has 47 chromosomes.
(C) Thalassemia — Incorrect. It is an autosomal recessive Mendelian disorder in which too little globin is made. The chromosome number is normal.
(D) Turner’s Syndrome — Correct. One X chromosome is missing, giving 45 chromosomes (44 + XO).
NCERT Extract:
Chromosomal Disorders – …
