Question

Mention the chromosomal abnormalities concerned with following conditions in humans
(a) Turner's syndrome (b) Klinefelter's syndrome (C) Down's syndrome

Answer 1

(A) Turner's syndrome: This disorder is caused due to the absence of one of the X chromosomes, i.e, 45 with XO, such females are sterile as ovaries are rudimentary besides other features including lack of other secondary sexual characters.

(B) Klinefelter's syndrome - This genetic disorder is caused due to the presence of an additional copy of X-chromosome resulting into a karyotype of 47, XXY. Such an individual has overall masculine development, however, the feminine development is also expressed.

(C) Down's syndrome - The cause of this genetic disorder is the presence of an additional copy of the chromosome number 21 (trisomy 21). The affected individual is short stature with small round head, furrowed tongue.