NEET2002ZoologyPrinciples of Inheritance and VariationActual
A diseased man marries a normal woman. They get three daughter and five sons. All the daughter were diseased and sons were normal. The gene of this disease is:
Options
- Asex-linked dominant
- Bsex-linked recessive
- Csex-limited character
- Dautosomal dominant
Correct answer
A. sex-linked dominant
Step-by-step solution
Father gives his X-chromosome to the daughter while Y-chromosome to the sons. In the case, only daughter and none of the sons are affected, the trait is X-linked. Since, daughters get the second copy of X -chromosomes from the mother who is normal and hence does not carry the affected allele of the trait. The trait is expressed in daughters under heterozygous condition, hence it is a X-linked dominant trait