Ataxia-oculomotor apraxia-2 (AOA2, also referred to as autosomal recessive spinocerebellar ataxia-1) has been associated with mutations in the SETX gene. AOA2 is allelic with ALS4, a motor neuron disorder of early onset and autosomal dominant inheritance. The SETX gene (26 exons) spans ~94 kb of genomic DNA and is located on chromosome 9q34.13, ~134 Mb from the p-telomere.
Ataxia-oculomotor apraxia 1 (AOA1) has been associated with mutations in the APTX gene. The APTX gene (9 exons) spans ~29 kb of genomic DNA and is located on chromosome 9p13.3, ~33 Mb from the p-telomere.
Mutations in the FXN gene are involved in Friedreich’s ataxia. The FXN gene (6 exons) spans ~65 kb of genomic DNA and is located on chromosome 9q13, ~70.9 Mb from the p-telomere. Please note that the major cause of Friedreich’s ataxia is an expansion of an intronic trinucleotide repeat, which cannot be detected with this P316-B2 Recessive Ataxias probemix.
The P316-B2 probemix contains probes for each exon of the APTX and SETX genes and for 5 out of 6 FXN exons. In addition, 9 reference probes are included in this probemix, detecting different autosomal chromosomal locations.