The Genetics of Fragile X Syndrome

This article discusses one of the most common forms of inherited mental disabilities in humans, Fragile X Syndrome. This syndrome is an X-linked trait, so generally males and females who inherit two genes for this trait are affected more than female carriers are. The severity of symptoms can vary in anyone who has this abnormality. The severity is dependent on how many codon repeats are found on the FMR1 gene on the X chromosome.

Fragile X Syndrome causes affected individuals to not make enough of a protein called fragile x mental retardation protein. This protein attaches to ribosomes between the 30s and 50s subunits to regulate protein synthesis. Before this research, done at UC San Diego, scientists only knew that a deficiency of this protein resulted in proteins that regulate brain functions being synthesized incorrectly. The fact the the protein binds between the 30s and 50s subunits of the ribosome is important, as new proteins are synthesized by passing mRNA through the two subunits. These proteins are imperative to normal cognitive function in humans-and fruit flies. Researchers used fruit flies in the laboratory to map where the protein binds to the ribosomes. This information will hopefully provide the tools necessary in the future to create new treatments for this affliction and help restore at least some cognitive function in those who have lost it.

Secondary article