Sepulveda R L, Heiba I M, Navarrete C, Elston R C, Gonzalez B, Sorensen R U
National Institute of Respiratory Diseases and Thoracic Surgery, Santiago, Chile.
Tuber Lung Dis. 1994 Apr;75(2):138-43. doi: 10.1016/0962-8479(94)90043-4.
Studies showing significantly higher concordance of tuberculosis among monozygotic twins than dizygotic twins have provided support for genetically determined susceptibility to tuberculosis.
We wished to explore whether the development of delayed type hypersensitivity to tuberculin after newborn BCG immunization of twins suggested genetic regulation of the response to BCG in humans.
Our study population consisted of 17 monozygotic twin pairs, 18 dizygotic twin pairs, and 64 single infants 3-34 months of age from Santiago, Chile. All had a BCG scar and were tuberculin tested by one trained nurse.
The mean birth weight of both groups of twins was significantly lower than that of singletons and the percentage of individuals who failed to respond to tuberculin was approximately twice as high in twins as in singletons. After adjustment for birth weight and age by regression analysis, it was found that the distribution of tuberculin reactivity in both monozygotic and dizygotic twins was not significantly different from that of singletons. Both twin pair correlations is adjusted tuberculin reactivity were significantly greater than zero (P < 0.01) and led to a heritability estimate of 0.28. However, the monozygotic twin correlation was not significantly larger than the dizygotic twin correlation so that heritability is poorly estimated.
These results are consistent with a genetic regulation of the response to newborn BCG immunization in humans by a mechanism capable of producing similar responses in identical and nonidentical twins alike.
研究表明，单卵双胞胎中结核病的一致性显著高于双卵双胞胎，这为结核病的遗传易感性提供了支持。
我们希望探讨双胞胎新生儿接种卡介苗后对结核菌素迟发型超敏反应的发展是否表明人类对卡介苗反应的遗传调控。
我们的研究对象包括来自智利圣地亚哥的17对单卵双胞胎、18对双卵双胞胎以及64名3至34个月大的单胎婴儿。所有人都有卡介苗接种疤痕，并由一名经过培训的护士进行结核菌素检测。
两组双胞胎的平均出生体重均显著低于单胎婴儿，且对结核菌素无反应的个体比例在双胞胎中约为单胎婴儿的两倍。通过回归分析对出生体重和年龄进行调整后，发现单卵双胞胎和双卵双胞胎中结核菌素反应性的分布与单胎婴儿没有显著差异。调整后的结核菌素反应性的双胞胎对相关性均显著大于零（P < 0.01），遗传度估计为0.28。然而，单卵双胞胎的相关性并不显著大于双卵双胞胎的相关性，因此遗传度估计不准确。
这些结果与人类对新生儿卡介苗接种反应的遗传调控一致，其机制能够在同卵和异卵双胞胎中产生相似的反应。
