Kennedy’s disease is a degenerative disease transmitted in a X-linked recessive mode. The case of two sisters who both inherited two pathological alleles of the gene encoding the androgen receptor (AR) is reported by Norwegian researchers :
- both sisters had received a pathological allele from their mother, herself a transmitter, and another pathological allele from their father, himself suffering from the disease,
- their respective genotype therefore corresponded to 43/43 and 43/45 repeats of CAG triplets
- despite this composite heterozygosity, the phenotype observed with a 21-year follow-up was relatively mild, the symptomatology being limited to tremor of the extremities and fasciculations, all associated with chronic pain and cramps with minimal changing over time.
