SNP Shot: Genomic Insights

Congenital adrenal hyperplasia (CAH) caused by 11-beta-hydroxylase deficiency is a condition affecting the adrenal glands, which are located above the kidneys. These glands produce vital hormones that control numerous bodily functions. In individuals with this type of CAH, the adrenal glands produce an excess of androgens, which are male sex hormones. 11-beta-hydroxylase deficiency is one cause of the larger group of disorders called congenital adrenal hyperplasia.

There are two forms of CAH due to 11-beta-hydroxylase deficiency: the classic form and the non-classic form. The classic form is the more serious of the two.

Females with the classic form of 11-beta-hydroxylase deficiency-related CAH often have ambiguous genitalia at birth. However, their internal reproductive organs develop normally. Both males and females with the classic form experience early puberty, including the development of facial and pubic hair, a deeper voice, acne, and a rapid growth spurt. This early growth spurt can ultimately lead to reduced growth and shorter height in adulthood. Furthermore, approximately two-thirds of those with the classic form of CAH due to 11-beta-hydroxylase deficiency develop high blood pressure (hypertension), typically within the first year of life.

Females with the non-classic form of CAH due to 11-beta-hydroxylase deficiency have normal female genitalia. Later in life, they may experience excessive hair growth (hirsutism) and irregular menstrual cycles. Males with the non-classic form generally show no symptoms, although some may have short stature. High blood pressure is not associated with the non-classic form of CAH due to 11-beta-hydroxylase deficiency.

Inheritance:

This condition follows an autosomal recessive inheritance pattern. This means that an individual must inherit a mutated copy of the gene from both parents to be affected. The parents, who each carry one copy of the mutated gene, usually do not exhibit any symptoms of the condition.