Question

Hemophilia disease is linked with
A) Sex chromosome.
B) Autosome
C) Bacteria
D) Virus

Answer 1

Hint: We know that humans have 23 pairs of chromosome, out of which 22 are autosomal and 1 are sex chromosome. The chromosomes are XX in female and XY in male. Hemophilia is an inheritable disease and is caused due to the mutation in the genes.

Complete answer:
To answer this question we must first know about the disease hemophilia.
Hemophilia is a disease in which the blood doesn’t have the required anticoagulant(the agent which helps in coagulation of blood and stops bleeding by forming blood clot). Due to this excessive bleeding occurs after an injury and this may lead to the death of an individual if not taken proper precautions.

Hemophilia is of three types-
Hemophilia A – It occurs due to lack of factor Vlll i.e. antihemophilic globulin (AHG) .
Hemophilia B – It occurs due to lack of factor lX i.e. plasma thromboplastin compound (PTC).
Hemophilia C - It occurs due to lack of factor Xl i.e. plasma thromboplastin antecedent (PTA) .
The chromosome on which this disease or mutation occurs is the X – chromosome. Now we know that X- chromosome is a sex chromosome and so Hemophilia automatically becomes a sex linked disease.

Autosomal disease are the disease which are linked with mutation of genes on the autosome chromosome i.e. the rest 21 chromosomes which are same in humans . For example- Huntington disease.

Bacteria and viruses can also bring about mutation. They can lead to inversion or reversion of the segment of the DNA. Most commonly cancer is caused due to viral and bacterial induced mutations.
So from the above discussion , it is clear that hemophilia is linked with sex chromosome.

Thus the correct answer is option ‘A’.

Note: Hemophilia or bleeder's disease was discovered by John Otto in 1803 . It is found rare in females as both of the X chromosomes should have the mutation. The genes of hemophilia are so lethal that the affected female dies during the embryonic stage as this gene comes in homologous condition.