MRCP UK EXAMINATIONS

Detailed explanation-1: -If two copies of the abnormal gene are present, disease may develop. However, if only one abnormal gene is needed to produce a disease, it leads to a dominant hereditary disorder.

Detailed explanation-2: -An autosomal recessive disorder means two copies of an abnormal gene must be present in order for the disease or trait to develop.

Detailed explanation-3: -There are well over 6, 000 known genetic disorders, and new genetic disorders are constantly being described in medical literature. More than 600 genetic disorders are treatable.

Detailed explanation-4: -Some of the more common single-gene disorders include cystic fibrosis, hemochromatosis, Tay-Sachs, and sickle cell anemia. Even though these diseases are primarily caused by a single gene, several different mutations can result in the same disease but with varying degrees of severity and phenotype.

Detailed explanation-5: -You need only one altered gene to be affected by this type of disorder. A person with an autosomal dominant disorder-in this case, the father-has a 50% chance of having an affected child with one altered gene. The altered gene is known as the dominant gene.