In a family, the father has widely spaced eyes, increased facial hair and deafness. One of the three children has deafness with similar facial features. The mother is normal. Most likely pattern of inheritance in this case is
A. Autosomal dominantB. Autosomal recessive
C. X-linked dominant
D. X-linked recessive
Ans. A. Autosomal dominant
Here
father is affected and one of three children is affected. Mother is normal. It
is not clear whether male or female child is affected.
• Autosomal dominant disorders: Any
child has 50% chances of
inheriting the disease.
• It cannot be Autosomal recessive disorder as here both father and children
are affected. And homozygous father and normal mother will have asymptomatic
children carrier.
• X-linked dominant disorder: Affected
father will not affect male child. It affects only daughter.
• X-lirilced recessive disorder: Affected father will not affect male child.
Female child will be affected only if mother is also carrier.
* Therefore most likely Answer is autosomal dominant disorder
