Mendelian Disorders in Humans
Mendelian Disorders in Humans: Overview
This Topic covers sub-topics such as Thalassemia, Sickle-cell Anaemia, Cystic Fibrosis, Haemophilia, Phenylketonuria, Colour Blindness, Genetic Disorders, Pedigree Analysis, Autosomal Dominant Disorders and, Mendelian Disorders
Important Questions on Mendelian Disorders in Humans
Choose the Mendelian disorder that is a sex-linked recessive disorder.

What would be the genotype of:
(i) An individual who is carrier of sickle cell anaemia gene but apparently unaffected.
(ii) An individual affected with the disease.

Which of the following species is rarely haemophilic?

Recently a girl baby has been reported to suffer from haemophilia. Her mother was not suffering from the disease. The genotype of her father would be:

The trait can be described as:


Sickle cell anaemia is characterised by

Given below is a pedigree chart showing the inheritance of a certain sex-linked trait in humans.
The trait traced in the above pedigree chart is

Genes of which one of the following is present exclusively on the X-chromosome in humans?


Which one of the following symbols represents mating between relatives in human pedigree analysis?

Which of the following symbol represents normal parents with affected male child ?

Study the given pedigree chart and find the genotypes of the individuals II and III.

In humans, attached earlobes are a dominant feature over free earlobes while hypertrichosis of the ear is a holandric (-linked) feature. A man with attached earlobes and extensive hair on pinna married a woman having free earlobes. The couple had one son with attached earlobes and hairy pinna, another son with free earlobes and hairy pinna and two daughters with attached earlobes. One of the daughters married a man with free earlobes and sparse hair on pinna. They had two sons. What would be the characteristics of their pinnae? What would be characteristic of their two daughters?

Identify the incorrect statement about pedigree analysis.

Select the correct matching regarding standard symbol of pedigree analysis
Column-I | Column-II | ||
(A) | ![]() |
(1) | Female |
(B) | ![]() |
(2) | Male |
(C) | ![]() |
(3) | Mating |
(D) | ![]() |
(4) | Sex unspecified |

The method for analyzing inheritance pattern of traits in human being is

Which of the following is an autosomal dominant trait?

Which of the following amino acid is not present in first six amino acids in affected -chain of Haemoglobin in sickle cell anaemia?

Which of the following is sex-linked recessive disorder?
