Question

Autosomal mutant allele Hbs causes
A. Thalassemia
B. Albinism
C. Sickle cell anaemia
D. Agammaglobulinemia

Answer 1

Gene defects are caused by single-gene mutations, a combination of gene mutations and environmental causes, or by chromosomal damage, i.e. variations in the number or arrangement of gene-carrying structures of whole chromosomes. Autosomal mutant allele alters the normal structure of the haemoglobin.

Complete answer: The building blocks of heredity are chromosomes. From parent to an infant, they are transferred. A mutation is a change in a gene or genes that often occurs due to various factors. The mutation alters instructions of the gene to produce a protein so that the protein does not function properly or is totally absent. A medical condition called the genetic disorder may occur due to this. An example is sickle cell anaemia. The sickle cell anaemia is an inherited red blood cell condition in which the body does not have enough red blood cells to retain oxygen. SCD is a recessive autosomal disorder. To get the disorder, you need two copies of the gene. You are said to have a sickle cell trait if you have only one copy of the gene. Sickle cell anaemia occurs due to mutation in Hbs gene. It occurs when you inherit both parent’s copies of the haemoglobin S gene.
a) Thalassemia major and thalassemia intermedia are inherited in an autosomal recessive pattern, which means that mutations have both copies of the HBB gene in each cell.
b) Albinism is a rare category of genetic conditions that involve little to no colour in the skin, hair and eyes. Albinism is associated with issues with vision as well. Albinism occurs by a gene mutation on the X chromosome is the most common type.
c) X-linked agammaglobulinemia is caused and inherited in an X-linked recessive manner by modifications (mutations) in the BTK gene.
Thus, the correct answer is option C.

Note: Not all genetic disorders lead to death directly; there are no proven treatments for genetic disorders. Many genetic conditions, such as down syndrome, impact development stages, while others contribute to solely physical symptoms, such as muscular dystrophy. Other diseases display no symptoms until adulthood, such as Huntington’s disease.