Identification of Tau and SOD1 gene mutation in a small Chinese Han pedigree of adult amyotrophic lateral sclerosis.

We report the clinical profile, and a brief investigation of SOD1 and Tau gene mutation from a small Chinese Han pedigree of adults with amyotrophic lateral sclerosis (ALS), which consisted of 32 familial members with 6 affected individuals spanning five generations, and presenting autosomal dominant genetic mode. The mean age of onset was 36.6 ± 15.9 years, and disease duration was 6 months to more than 5 years, the average survival was 16.1 ± 8.2 months. There were 5 patients with an early disease onset, rapid progressive course and short survival, and 1 patient with late onset, slow progressive course and long survival in the kindred. ALS patients began to suffer with weakness and muscle atrophy in one side of a lower extremity, which then spread to the upper extremity, the opposite side and bulbar muscles. All patients had spinal onset type. Muscle stretch reflexes were absent or weak in the upper limbs and accentuation in the lower limbs; pathological signs in the lower limbs were positive. Electromyography disclosed ongoing denervation muscle potentials in the four extremities. Brain and spinal MRI did not show any abnormal signal. A 5 exons mutation of SOD1 in all affected individuals was identified using SSCP. Polymorphisms of partial risk regions in 3',5' UTR, and in introns 9, 10, 11, 12 of the Tau gene in the affected and normal family members and in 70 healthy controls were examined by DNA sequencing. Routine exons mutation of SOD1 was not detected, but one single nucleotide polymorphism of A to G at 138278 at 3' UTR of the Tau gene was shown to significantly over-express in fALS familial members.