Dyslexia-related loci are significantly associated with language and literacy in Chinese –English bilingual Hong Kong Chinese twins

This study explores the genetic overlap between Chinese and English word reading, vocabulary knowledge and spelling, and aims at replicating the association in a unique cohort of bilingual (Chinese –English) Hong Kong Chinese twins. Our result showed an almost complete genetic overlap in vocabulary knowledge (r2 = 0.995), and some genetic overlaps in word reading and spelling (r2 = 0.846, 0.687) across the languages. To investigate the region near rs2624839, we tested proxy SNPs (rs1005678, rs12632110 and rs12494414) at the population level (n = 305–308) and the within-twin level (n = 342–344 [171–172 twin pairs]). All the three SNPs showed significant associations with quantitative Chinese and English vocabulary knowledge (p <  0.05). The strongest association after multiple testing correction was between rs12494414 and English vocabulary knowledge at the within-twin level (p = 0.004). There was a trend of associations with word reading and spelling in English but not in Chinese. Our result suggested that the region near rs2624839 is one of the common genetic factors across English and Chinese vocabulary knowledge and unique factors of English word reading and Engli sh spelling in bilingual Chinese twins. A larger sample size is required to validate our findings. Further studies on the relationship between variable expression ofSEMA3F, which is important to neurodevelopment, and language and literacy are encouraged.
Source: Human Genetics - Category: Genetics & Stem Cells Source Type: research