Cohen Zvi, Kalichman Leonid, Kobyliansky Eugene, Malkin Ida, Almog Eliana, Livshits Gregory
Department of Traumatology and Orthopaedic Surgery A, Tel Aviv Sourasky Medical Center, Israel.
Med Sci Monit. 2003 Mar;9(3):MT13-20.
Bone geometry (BG) and size (BS) are important factors in determining bone fragility. Previous studies have suggested that more than half of BG and BS variation is genetically determined. The possible chromosomal locations of genes involved in BS and BG determination have not been explored. We evaluated the extent and mode of inheritance of the radiographic hand BS index (BSI) and the metacarpal cortical index (MCI), and tested the hypothesis of linkage between these traits and the 11q 12-13 chromosomal region.
MATERIAL/METHODS: Hand radiographs and blood samples were collected from 1190 individuals belonging to 349 Chuvasha nuclear families (Russian Federation). Segregation analysis was conducted on a total sample. Transmission disequilibrium testing (TDT) and model-based linkage analyses (MBLA) were performed on a sub-sample of 163 families.
The hypothesis of a major gene effect was confirmed for both studied traits. The best-fitting models were Mendelian, with an additive type of inheritance. The inferred major gene explained 50% of the CI and 40% of the BSI variation. The TDT and MBLA results did not permit confirmation of hypotheses about linkage between hand BSI and the 11q 12-13 chromosomal region, but a possible linkage between CI and that region cannot be ruled out.
We support the hypothesis of a major gene effect in the heritability of BSI and MCI. We provide suggestive evidence for possible linkage disequilibrium between MCI and the 11q12-13 chromosomal segment (marker D11S1983), but not for a linkage between BSI and this
骨几何形态（BG）和骨大小（BS）是决定骨脆性的重要因素。既往研究表明，超过一半的BG和BS变异由基因决定。尚未探究参与BS和BG决定的基因的可能染色体定位。我们评估了手部X线片骨大小指数（BSI）和掌骨皮质指数（MCI）的遗传程度和遗传模式，并检验了这些性状与11q12 - 13染色体区域之间连锁的假设。
材料/方法：收集了来自俄罗斯联邦楚瓦什族349个核心家庭的1190名个体的手部X线片和血样。对全部样本进行分离分析。对163个家庭的子样本进行传递不平衡检验（TDT）和基于模型的连锁分析（MBLA）。
两种研究性状均证实了主基因效应的假设。最佳拟合模型为孟德尔遗传模型，遗传方式为加性遗传。推断的主基因解释了50%的CI变异和40%的BSI变异。TDT和MBLA结果不能证实关于手部BSI与11q12 - 13染色体区域之间连锁的假设，但不能排除CI与该区域之间可能存在的连锁。
我们支持BSI和MCI遗传力存在主基因效应的假设。我们提供了提示性证据，表明MCI与11q12 - 13染色体片段（标记D11S1983）之间可能存在连锁不平衡，但未发现BSI与该区域之间存在连锁。
