Posthuma Danielle, Visscher Peter M, Willemsen Gonneke, Zhu Gu, Martin Nicholas G, Slagboom P Eline, de Geus Eco J C, Boomsma Dorret I
Department of Biological Psychology, Vrije Universiteit, Amsterdam, The Netherlands.
Behav Genet. 2006 Jan;36(1):12-7. doi: 10.1007/s10519-005-9007-x. Epub 2005 Dec 9.
: The aim of the study was to perform a genetic linkage analysis for eye color, for comparative data. Similarity in eye color of mono- and dizygotic twins was rated by the twins' mother, their father and/or the twins themselves. For 4,748 twin pairs the similarity in eye color was available on a three point scale ("not at all alike"-"somewhat alike"-"completely alike"), absolute eye color on individuals was not assessed. The probability that twins were alike for eye color was calculated as a weighted average of the different responses of all respondents on several different time points. The mean probability of being alike for eye color was 0.98 for MZ twins (2,167 pairs), whereas the mean probability for DZ twins was 0.46 (2,537 pairs), suggesting very high heritability for eye color. For 294 DZ twin pairs genome-wide marker data were available. The probability of being alike for eye color was regressed on the average amount of IBD sharing. We found a peak LOD-score of 2.9 at chromosome 15q, overlapping with the region recently implicated for absolute ratings of eye color in Australian twins [Zhu, G., Evans, D. M., Duffy, D. L., Montgomery, G. W., Medland, S. E., Gillespie, N. A., Ewen, K. R., Jewell, M., Liew, Y. W., Hayward, N. K., Sturm, R. A., Trent, J. M., and Martin, N. G. (2004). Twin Res. 7:197-210] and containing the OCA2 gene, which is the major candidate gene for eye color [Sturm, R. A. Teasdale, R. D, and Box, N. F. (2001). Gene 277:49-62]. Our results demonstrate that comparative measures on relatives can be used in genetic linkage analysis.
本研究的目的是对眼睛颜色进行遗传连锁分析，以获取比较数据。单卵双胞胎和双卵双胞胎眼睛颜色的相似性由双胞胎的母亲、父亲和/或双胞胎自身进行评定。对于4748对双胞胎，眼睛颜色的相似性按三点量表进行评定（“完全不像” - “有些像” - “完全一样”），未对个体的绝对眼睛颜色进行评估。双胞胎眼睛颜色相似的概率通过所有受访者在几个不同时间点的不同回答的加权平均值来计算。同卵双胞胎（2167对）眼睛颜色相似的平均概率为0.98，而异卵双胞胎的平均概率为0.46（2537对），这表明眼睛颜色具有很高的遗传度。对于294对异卵双胞胎，可获得全基因组标记数据。眼睛颜色相似的概率根据平均共享的同源染色体片段量进行回归分析。我们在15号染色体q区发现了一个最高对数优势分数为2.9的峰值，该区域与最近在澳大利亚双胞胎中涉及眼睛颜色绝对评定的区域重叠[朱，G.，埃文斯，D. M.，达菲，D. L.，蒙哥马利，G. W.，梅德兰，S. E.，吉莱斯皮，N. A.，尤恩，K. R.，朱厄尔，M.，刘，Y. W., 海沃德，N. K.，斯特姆，R. A.，特伦特，J. M.，以及马丁，N. G.（2004年）。双胞胎研究。7:197 - 210]，并且该区域包含OCA2基因，这是眼睛颜色的主要候选基因[斯特姆，R. A.，蒂斯代尔，R. D，以及博克斯，N. F.（2001年）。基因。277:49 - 62]。我们的结果表明，亲属间的比较测量可用于遗传连锁分析。
