Question

Which one of the following is holandric inheritance?

• A. Haemphilia
• B. Epidermolysis
• C. Webbed toes
• D. Turner's Syndrome

Answer 1

Answer: (C)

Webbed toes

Y-linked traits show holandric inheritance as their governing genes are present on loci found only on the Y chromosome and the traits are holandric traits (found only in males). Hemophilia is X-linked recessive disorder. The associated genes are located on the X chromosome; it does not show holandric inheritance. The absence of one X-chromosome causes Turner's syndrome which is represented as 44 +XO; the individual is sterile females as they lack one X-chromosome. This makes it negative answer for holandric inheritance. Epidermolysis is an autosomal dominant disorder of skin caused by heterozygous mutation in either the keratin-5 gene present on chromosome 12 or the keratin-14 gene present on chromosome 17; it does not show holandric inheritance. Webbed toes, characterized by the presence of skin/tissues between toes, are caused by genes on the Y chromosome and thus are carried and transmitted only by males, i.e., it shows holandric inheritance. The correct answer is C.