GJ gene family

Genes in the GJ gene family provide instructions for producing proteins called connexins. Connexins are one part (subunit) of a structure called a connexon that is found within cell membranes. Six connexins make up one connexon. Connexons allow for cell-to-cell communication by joining with connexons of other cells to form a channel. Many channels clustered together form a gap junction. Gap junctions speed the transport of nutrients, charged particles (ions), and other small molecules that carry signals between cells. Communication through gap junctions helps regulate many different processes, including heart function, cell growth and specialization, and development before birth.

There are 21 known genes in the human GJ gene family. The genes in this family are designated by the letters GJ and an additional letter and number specific to that particular gene, for example GJB2.

Changes in GJ genes are associated with disorders that affect different parts of the body. Specifically, mutations in the GJB1 gene cause one form of Charcot-Marie-Tooth disease, an inherited condition that affects the nervous system. Additionally, mutations in the GJA1 gene cause oculodentodigital dysplasia, a condition that primarily affects the development of the eyes, teeth, and fingers. Other conditions associated with mutations in the GJ genes include deafness, clouding of the lens of the eyes (cataracts), and various skin disorders.