Stevenson J, Graham P, Fredman G, McLoughlin V
J Child Psychol Psychiatry. 1987 Mar;28(2):229-47. doi: 10.1111/j.1469-7610.1987.tb00207.x.
The reading skills of 285 pairs of 13-year-old twins drawn from the general population were studied. The twins were independently tested using standardized measures of intelligence, reading and spelling ability. The genetic contribution to reading ability was assessed by examination of correlations in monozygotic (MZ) and same-sex dizygotic (DZ) twins, and by analysing differences between MZ and DZ twins in concordance of reading disability rates. The results suggested that, at this age, genetic factors play only a moderate role in general reading backwardness or specific reading retardation. However, when spelling ability was investigated, a heritability of 0.53 was obtained, increasing to 0.75 when intelligence was controlled. Strong genetic influences on spelling were also found when concordance rates for spelling disability were compared for MZ and DZ pairs.
对从普通人群中抽取的285对13岁双胞胎的阅读技能进行了研究。使用标准化的智力、阅读和拼写能力测试对双胞胎进行独立测试。通过检查同卵双胞胎（MZ）和同性异卵双胞胎（DZ）之间的相关性，以及分析MZ和DZ双胞胎在阅读障碍率一致性方面的差异，评估遗传因素对阅读能力的影响。结果表明，在这个年龄，遗传因素在一般阅读落后或特定阅读迟缓中仅起中等作用。然而，当研究拼写能力时，遗传率为0.53，在控制智力后增加到0.75。当比较MZ和DZ对的拼写障碍一致性率时，也发现了对拼写的强烈遗传影响。
