Thirty-seven CAG repeats in the androgen receptor gene in two healthy individuals.
X-linked recessive spinobulbar muscular atrophy (SBMA) is an adult-onset X-linked neurodegenerative disease, characterised by muscular atrophy, bulbar symptoms and endocrinological disturbances. SBMA is caused by the expansion of a CAG repeat in the androgen receptor gene. The maximum number of CAG repeats found in a healthy person is 35 while the minimum number of repeats found in SBMA patients is 38. We have identified a 46-year-old man from an SBMA family with 37 CAG repeats who until now is clinically unaffected. Interestingly, his 85-year-old mother who has the genotype 37/51 CAG repeats is clinically unaffected as well. These results suggest an exactly defined border between normal and disease alleles.
Klinik und Poliklinik für Neurologie Westfälische Wilhelms Universität Münster, Germany. gkuhlen@uni-muenster.de
G
G
Kuhlenbäumer
W
W
Kress
E B
EB
Ringelstein
F
F
Stögbauer
D000368:Aged; D005260:Female; D005838:Genotype; D006801:Humans; D008297:Male; D008875:Middle Aged; D009134:Muscular Atrophy, Spinal / Q000235:genetics* / Q000473:pathology; D010375:Pedigree; D010641:Phenotype; D011944:Receptors, Androgen / Q000235:genetics*; D019680:Trinucleotide Repeat Expansion / Q000235:genetics*
D011944:Receptors, Androgen