Hypertension, or high blood pressure, appears to have a strong genetic contribution. It can occur as an isolated symptom, in the case of essential hypertension, or as one of many symptoms in a variety of genetic syndromes. Syndromes that affect the kidneys often include hypertension. The genetics of hypertension is complicated because variations in many different genes contribute to hypertension.
Essential Hypertension
The various contributions of genes and environment on hypertension have been studied since at least the early 1960s. Whereas it was originally thought that a single gene, passed on from parent to child, determined the development of isolated hypertension, it now appears that the influence of multiple genes and multiple environmental factors combine to determine a person's blood pressure. A person with essential hypertension, or high blood pressure with no identifiable cause, probably develops the condition by inheriting one or more genetic factors that predispose to hypertension and following a lifestyle that contributes to hypertension.
Neurofibromatosis Type I
Neurofibromatosis type I is a genetic disorder characterized by cafe-au-lait spots (dark spots on the skin) and tumors of the skin, among other symptoms. Some individuals with neurofibromatosis also have hypertension, often due to the presence of a pheochromocytoma, which is a tumor of the adrenal gland. Neurofibromatosis is an autosomal dominant disease, which means that a mutation in one gene that can be passed from parent to child causes the condition. Each child of a person with an autosomal dominant disease has a 50 percent chance of inheriting the disease.
Adult Polycystic Kidney Disease
Adult polycystic kidney disease, or APKD, is another autosomal dominant genetic disease. Unlikely neurofibromatosis, which is caused by a mutation in one specific gene, APKD can be caused by mutations in at least three different genes. The symptoms of APKD include cysts in the kidneys, cysts in other organs including the liver, and aneurysms in the brain. People with APKD are not born with kidney cysts; they develop over time, leading to progressive kidney failure. According to GeneReviews, about 50 percent of individuals with APKD have end-stage renal disease by age 60. Kidney failure is a major contributor to hypertension, so people with APKD develop high blood pressure as their disease progresses.
Von Hippel-Lindau Syndrome
Von Hippel-Lindau, or VHL, syndrome is an autosomal dominant cancer syndrome, caused by mutations in the VHL gene and possibly moderated by variations in another gene called cyclin D1. VHL causes a variety of malignant and benign tumors, primarily in the retina, kidneys, cerebellum, pancreas and adrenal glands. As with neurofibromatosis, adrenal gland tumors often go along with hypertension. Tumors of the cerebellum also contribute to hypertension in VHL.
References
- "British Medical Journal"; Inheritance of Hypertension; June 1968
- Online Mendelian Inheritance in Man: Hypertension, Essential
- Online Mendelian Inheritance in Man: Neurofibromatosis, Type I
- GeneReviews: Polycystic Kidney Disease, Autosomal Dominant
- Online Mendelian Inheritance in Man: Von Hippel-Lindau Syndrome
