A mutation is a change in the DNA of an organism. The change may or may not result a change to the physical characteristics (or phenotype) of the organism. Mutations that occur in a gamete (sperm or eggs) can be passed to the next generation, whereas mutations that occur in body (or 'somatic') cells may be harmless or may result in a disease such as cancer. Mutations can result in DNA being copied incorrectly. Mutagens can also cause mutations.

A point mutation is a change in one base in the genetic code. The change of one base to a different base (often caused by the DNA being copied incorrectly)-this is called a substitution mutation.

Identify the inheritable disorders caused by mutation of genes in human beings:

Sickle Cell Anaemia and Thalassemia

The correct answer is Option (2) → Sickle Cell Anaemia and Thalassemia

Sickle Cell Anaemia and Thalassemia are inheritable disorders caused by mutations in specific genes related to hemoglobin production. These mutations are passed from parents to offspring through autosomal recessive inheritance, which makes them inheritable genetic disorders.

Turner's syndrome and Down's syndrome are not caused by gene mutations but rather by chromosomal abnormalities:

• Down’s Syndrome : The cause of this genetic disorder is the presence of an additional copy of the chromosome number 21 (trisomy of 21). This disorder was first described by Langdon Down (1866). The affected individual is short statured with small round head, furrowed tongue and partially open mouth. Palm is broad with characteristic palm crease. Physical, psychomotor and mental development is retarded.

  Turner’s Syndrome : Such a disorder is caused due to the absence of one of the X chromosomes, i.e., 45 with XO, Such females are sterile as ovaries are rudimentary besides other features including lack of other secondary sexual characters.

Only Sickle Cell Anaemia and Thalassemia are inheritable disorders caused specifically by gene mutations.