New Genetic Tests Available for Hereditary Ataxias

Several genetic tests, including repeat-expansion analysis for spinocerebellar ataxia (SCA), Friedreich ataxia, and other common forms of hereditary ataxia have been newly made available by GeneDx (Gaithersberg, MD). The repeat-expansion analysis may be done concurrently with single nucleotide variant testing.

Most types of adult-onset hereditary ataxia are caused by nucleotide repeat expansions within the DNA and are usually identified by specialized testing. The remaining types of hereditary ataxia may be caused by single nucleotide variants and copy number variants that can be identified by sequencing and deletion/duplication testing.  

Currently, genetic testing for adult-onset ataxia is limited to a small number of diagnostic laboratories, most of which offer only a portion of the relevant testing, have long turnaround times, and high out-of-pocket costs for patients. 

“Individuals with ataxia need more diagnostic testing options for genetic forms of the disease,” said Amanda Lindy, PhD, FACMG, director of neurogenetics, GeneDx. “Historically, genetic testing for ataxia has been limited, creating a barrier for some individuals to obtain testing. GeneDx’s expanded test offerings provide the flexibility of ordering single or multi-gene repeat expansion analyses, concurrently or reflexively, with a phenotypically driven expanded panel or an exome, thus covering the broadest possible differential, delivering more answers to patients and their families, and enabling precision medical management.”