Question

Which one of the following is holandric inheritance?
A. Haemophilia
B. Epidermolysis
C. Webbed toes
D. Turner’s Syndrome

Answer 1

Hint: The sex chromosomes in human are denoted by X and Y chromosomes. When an individual bears XX chromosomes, the sex is female while if XY chromosomes are present, the sex is male sex. Each chromosome contains genes. The genes located on Y chromosomes are called holandric genes.

Complete answer:
The genes present in the chromosomes are related to inheritance and heredity. The inheritance pattern of a particular character is determined by a gene which is located on one of the sex chromosomes.
The genes present exclusively on the X- chromosomes are known as X-linked genes and those genes that are present on the Y-chromosomes are known as holandric genes. The inheritance of these sex-linked genes are referred to as sex-linked inheritance.
The inheritance pattern of X-linked genes show a criss-cross pattern of inheritance. In this pattern, the X-linked recessive genes are passed from a male parent to the F2 male progeny through the F1 daughters. The F1 daughters are known as carriers. The most common examples of this type of inheritance are colour-blindness and haemophilia.
In the Y-linked inheritance, genes that are present in the non-homologous region of the Y chromosomes are passed directly from the males of one generation to the males of the other generation. The genes present in the Y chromosomes are related to expression of male characters.
The Y-linked gene inheritance is also known as holandric inheritance and the most common examples of diseases arising from this type of inheritance are webbed feet and hairy ears in males. Webbed feet is a condition where a net like webbing is present in between the toes, especially on the second and third toes of the individual. The genes of webbed feet is transferred from the father to the son and is a case of holandric inheritance.

> Hence, the option(C) is the correct option.

Note: Y-linked inheritance or holandric inheritance is a due to the inheritance of genes present on the Y genes. The Y chromosomes in human is related to the male sex and in the inheritance pattern of the genes, the son receives the gene from the father.