MAPT as a predisposing gene for sporadic amyotrophic lateral sclerosis in the Chinese Han population

A previous study of European Caucasian patients with sporadic amyotrophic lateral sclerosis demonstrated that a polymorphism in the microtubule-associated protein Tau （MAPT） gene was significantly associated with sporadic amyotrophic lateral sclerosis pathogenesis. Here, we tested this association in 107 sporadic amyotrophic lateral sclerosis patients and 100 healthy controls from the Chinese Han population. We screened the mutation-susceptible regions of MAPT- the 3＇ and 5＇ untranslated regions as well as introns 9, 10, 11, and 12 - by direct sequencing, and identified 33 genetic variations. Two of these, 105788 A 〉 G in intron 9 and 123972 T 〉 A in intron 11, were not present in the control group. The age of onset in patients with the 105788 A 〉 G and/or the 123972 T 〉 A variant was younger than that in patients without either genetic variation. Moreover, the pa- tients with a genetic variation were more prone to bulbar palsy and breathing difficulties than those with the wild-type genotype. This led to a shorter survival period in patients with a MAPT genetic variant. Our study suggests that the MAPT gene is a potential risk gene for sporadic amyotrophic lateral sclerosis in the Chinese Han population.

Association between DPP6 polymorphism and the risk of sporadic amyotrophic lateral sclerosis in Chinese patients

Background Amyotrophic lateral sclerosis （ALS） is a progressive degenerative disease characterized by the loss of motor neurons in the spinal cord, brainstem, and cerebral cortex, which results in muscle weakness, atrophy. Sporadic ALS （SALS） accounts for about 90% of ALS cases, but the etiology is largely unknown. Most of the researchers consider it to be a complex disease. There have been several genome-wide association （GWA） studies reporting several single nucleotide polymorphisms （SNPs） which are susceptible to ALS, but no data of Asians （including Chinese） yet. We investigate whether the polymorphism of rs10260404 in DPP6 gene is associated with SALS in Chinese Han origin to compare the ethnic differences between Chinese Han origin and other populations. Methods The genomic DNA was extracted from the leukocytes of whole blood samples in 58 Chinese Han patients with SALS and 52 healthy controls. The asymmetric PCR was processed in the presence of an unlabeled probe that contained the rs10260404 locus. The product was genotyped on a light scanner using high resolution melting method and some were confirmed with sequencing. Results The rs10260404 polymorphism was in Hardy-Weinberg equilibrium in patients and controls. The CC genotype and the C allele were similar in patients compared with healthy subjects and not associated with an increased risk of Chinese SALS patients （X^2=0.29, OR=1.26, 95% CI 0.55-2.87, P 〉0.05）. Conclusions The rs10260404 is not associated with ALS susceptibility in Chinese people with Han origin which may be due to ethnic differences. More study with large number of cases in Chinese population is really necessary.