Dworzynski Katharina, Remington Anna, Rijsdijk Frühling, Howell Peter, Plomin Robert
Department of Psychology, King's College London, Gower Street, London, UK.
Am J Speech Lang Pathol. 2007 May;16(2):169-78. doi: 10.1044/1058-0360(2007/021).
The contribution of genetic factors in the persistence of and early recovery from stuttering was assessed.
Data from the Twins Early Development Study were employed. Parental reports regarding stuttering were collected at ages 2, 3, 4, and 7 years, and were used to classify speakers into recovered and persistent groups. Of 12,892 children with at least 2 ratings, 950 children had recovered and 135 persisted in their stutter.
Logistic regressions showed that the rating at age 2 was not predictive of later stuttering, whereas ratings at ages 3 and 4 were. Concordance rates were consistently higher for monozygotic than for dizygotic twin pairs (with the exception of girls at age 3). At 3, 4, and 7 years, the liability to stuttering was highly heritable (h2 estimates of between .58 and .66). Heritability for the recovered and persistent groups was also high but did not differ from each other.
Stuttering appears to be a disorder that has high heritability and little shared environment effect in early childhood and for recovered and persistent groups of children, by age 7. The clinical implications of the findings are discussed.
评估遗传因素在口吃持续存在及早期恢复过程中的作用。
采用来自双胞胎早期发育研究的数据。收集了2岁、3岁、4岁和7岁时父母关于口吃情况的报告，并据此将儿童分为恢复组和持续组。在12,892名至少有两次评估的儿童中，950名儿童口吃已恢复，135名儿童口吃仍持续。
逻辑回归分析显示，2岁时的评估结果不能预测后期口吃情况，而3岁和4岁时的评估结果具有预测性。同卵双胞胎的一致率始终高于异卵双胞胎（3岁女孩除外）。在3岁、4岁和7岁时，口吃倾向具有高度遗传性（遗传度估计值在0.58至0.66之间）。恢复组和持续组的遗传度也很高，但两组之间没有差异。
口吃似乎是一种在幼儿期以及到7岁时的恢复组和持续组儿童中具有高遗传性且几乎没有共享环境影响的疾病。文中讨论了这些研究结果的临床意义。
