Vallejo R L, Bacon L D, Liu H C, Witter R L, Groenen M A, Hillel J, Cheng H H
United States Department of Agriculture, Agricultural Research Service, Avian Disease and Oncology Laboratory, East Lansing, Michigan 48823, USA.
Genetics. 1998 Jan;148(1):349-60. doi: 10.1093/genetics/148.1.349.
Marek's disease (MD) is a lymphoproliferative disease caused by the MD virus (MDV), which costs the poultry industry nearly $1 billion annually. To identify quantitative trait loci (QTL) affecting MD susceptibility, the inbred lines 6(3) (MD resistant) and 7(2) (MD susceptible) were mated to create more than 300 F2 chickens. The F2 chickens were challenged with MDV JM strain, moderately virulent) at 1 wk of age and assessed for MD susceptibility. The QTL analysis was divided into three stages. In stage 1, 65 DNA markers selected from the chicken genetic maps were typed on the 40 most MD-susceptible and the 40 most MD-resistant F2 chickens, and 21 markers residing near suggestive QTL were revealed by analysis of variance (ANOVA). In stage 2, the suggestive markers plus available flanking markers were typed on 272 F2 chickens, and three suggestive QTL were identified by ANOVA. In stage 3, using the interval mapping program Map Manager and permutation tests, two significant and two suggestive MD QTL were identified on four chromosomal subregions. Three to five loci collected explained between 11 and 23% of the phenotypic MD variation, or 32-68% of the genetic variance. This study constitutes the first report in the domestic chicken on the mapping of non-major histocompatibility complex QTL affecting MD susceptibility.
马立克氏病（MD）是一种由马立克氏病病毒（MDV）引起的淋巴细胞增生性疾病，每年给家禽业造成近10亿美元的损失。为了鉴定影响MD易感性的数量性状基因座（QTL），将近交系6(3)（MD抗性）和7(2)（MD易感）进行交配，产生了300多只F2代鸡。F2代鸡在1周龄时用MDV JM株（中等毒力）进行攻毒，并评估其MD易感性。QTL分析分为三个阶段。在第一阶段，从鸡遗传图谱中选择的65个DNA标记在40只最易感MD和40只最抗MD的F2代鸡上进行分型，通过方差分析（ANOVA）揭示了21个位于提示性QTL附近的标记。在第二阶段，将提示性标记加上可用的侧翼标记在272只F2代鸡上进行分型，通过ANOVA鉴定出三个提示性QTL。在第三阶段，使用区间定位程序Map Manager和置换检验，在四个染色体亚区域鉴定出两个显著的和两个提示性的MD QTL。收集到的三到五个基因座解释了MD表型变异的11%至23%，或遗传变异的32%至68%。本研究是国内鸡中关于影响MD易感性的非主要组织相容性复合体QTL定位的首次报道。
