Rodríguez Larralde A, Barral I
Laboratorio de Genética Humana, IVIC, Caracas, Venezuela.
Acta Cient Venez. 1998;49(3):134-43.
The genetic structure of Zulia State, Venezuela, was studied through the distribution of surnames from individuals above 40 years of age, obtained from the register of electors. The sample studied consisted in 440, 190 individuals and 10,423 different surnames. For each of the 81 counties of the State, the following estimators were calculated: percentage of the population included in surnames which appear only once (estimator A), percentage of the population included in the seven most frequent surnames (estimator B), the coefficient of consanguinity due to random isonymy phi ii, and Karlin and McGregort's ni (v), an estimator of migration. The correlation between phi ii and B was 0.92, indicating that 85% of the variation observed in the coefficient of consanguinity due to random isonymy is due to the seven most frequent surnames. The correlation between A and ni was 0.93, so that 86% of the variation observed in ni, is due to surnames which appear only once. On the other hand, correlations between A and B, and between phi ii and v were non significant (-0.08 and -0.17 respectively), meaning that they are measuring different features of population structure: B and phi ii, isolation, while A and v, migration. The most isolated counties of Zulia are localized towards the northwestern portion of the State, within the Venezuelan Guajira, although relative isolation is also observed in the southern counties. Isolation by distance is estimated through the correlation between the logarithmic transformations of Euclidean and geographic distances, giving a value of 0.63. This high value might be partially due to the barrier effect of the Lake of Maracaibo. Eight surnames with a focal distribution within Zulia were identified: Almarza, Badell, Bastidas, Bohórquez, Cardozo, Carmona, Espina and Matos. Carriers of these surnames have a high probability of having their origin at the counties where they are localized.
通过对40岁以上选民登记册中个人姓氏分布情况的研究，对委内瑞拉苏利亚州的遗传结构进行了分析。所研究的样本包括440,190个人和10,423个不同的姓氏。对于该州的81个县，分别计算了以下指标：仅出现一次的姓氏所涵盖的人口百分比（指标A）、七个最常见姓氏所涵盖的人口百分比（指标B）、随机同姓导致的近亲系数phi ii，以及卡林和麦格雷戈的ni (v)（一种迁移估计指标）。phi ii与B之间的相关性为0.92，这表明在随机同姓导致的近亲系数中观察到的85%的变异是由七个最常见的姓氏引起的。A与ni之间的相关性为0.93，因此在ni中观察到的86%的变异是由仅出现一次的姓氏引起的。另一方面，A与B之间以及phi ii与v之间的相关性不显著（分别为-0.08和-0.17），这意味着它们衡量的是人口结构的不同特征：B和phi ii衡量隔离程度，而A和v衡量迁移情况。苏利亚州最孤立的县位于该州的西北部，在委内瑞拉瓜希拉地区内，不过在南部的县也观察到了相对的隔离情况。通过欧几里得距离和地理距离的对数变换之间的相关性来估计距离隔离，得出的值为0.63。这个高值可能部分归因于马拉开波湖的屏障效应。在苏利亚州内确定了八个具有集中分布的姓氏：阿尔马扎、巴德尔、巴斯蒂达斯、博尔克斯、卡多佐、卡尔莫纳、埃斯皮纳和马托斯。这些姓氏的携带者极有可能起源于他们所在的县。
