Family-Based Analysis Combined with Case-Controls Study Implicate Roles of PCNT in Tourette Syndrome

ASH1L may contribute to the risk of Tourette syndrome: Combination of family-based analysis and case-control study

OBJECTIVE

Tourette syndrome (TS) is a childhood neurodevelopmental disorder caused by various genetic and environmental factors and presents with apparent genetic heterogeneity. As ASH1L potentially contributes to neurodevelopmental diseases, especially in TS, we aim to investigate the susceptibility of ASH1L on TS in the Chinese Han population.

METHODS

Three tag single nucleotide polymorphisms (SNPs) (rs5005770, rs12734374, and rs35615695) in ASH1L were screened in 271 TS nuclear family trios and 337 healthy subjects by the TaqMan assays real time. A case-control study combined with family-based analysis was applied to study the genetic susceptibility of common variants of ASH1L.

RESULTS

The results revealed a significant over-transmission of rs35615695 and rs5005770 (for rs35615695, transmission disequilibrium test, χ²  = 57.375, p = .000, HHRR, χ²  = 4.807, p = .028; for rs5005770, HRR, χ²  = 4.116, p = .042, HHRR, χ²  = 8.223, p = .004) in family-based study. Furthermore, rs5005770 and rs35615695 still remained significant after Bonferroni correction (p < .017). However, the two SNPs (rs5005770 and rs35615695) were found not to be associated with TS in case-control study.

CONCLUSIONS

Our study suggests that ASH1L may contribute to TS susceptibility in the Han Chinese population and involved in TS development as a risk factor.

Hearing Function: Identification of New Candidate Genes Further Explaining the Complexity of This Sensory Ability

To date, the knowledge of the genetic determinants behind the modulation of hearing ability is relatively limited. To investigate this trait, we performed Genome-Wide Association Study (GWAS) meta-analysis using genotype and audiometric data (hearing thresholds at 0.25, 0.5, 1, 2, 4, and 8 kHz, and pure-tone averages of thresholds at low, medium, and high frequencies) collected in nine cohorts from Europe, South-Eastern USA, Caucasus, and Central Asia, for an overall number of ~9000 subjects. Three hundred seventy-five genes across all nine analyses were tagged by single nucleotide polymorphisms (SNPs) reaching a suggestive p-value (p < 10⁻⁵). Amongst these, 15 were successfully replicated using a gene-based approach in the independent Italian Salus in the Apulia cohort (n = 1774) at the nominal significance threshold (p < 0.05). In addition, the expression level of the replicated genes was assessed in published human and mouse inner ear datasets. Considering expression patterns in humans and mice, eleven genes were considered particularly promising candidates for the hearing function: BNIP3L, ELP5, MAP3K20, MATN2, MTMR7, MYO1E, PCNT, R3HDM1, SLC9A9, TGFB2, and YTHDC2. These findings represent a further contribution to our understanding of the genetic basis of hearing function and its related diseases.