Linkage disequilibrium between the fragile X mutation and two closely linked CA repeats suggests that fragile X chromosomes are derived from a small number of founder chromosomes.
Linkage disequilibrium between the fragile X mutation and two closely linked CA repeats suggests that fragile X chromosomes are derived from a small number of founder chromosomes.
复制标题
脆性 X 突变和两个紧密连锁的 CA 重复之间的连锁不平衡表明，脆性 X 染色体源自少数创始染色体。
DOI：
--
复制
发表时间：
1993
影响因子：
9.8
通讯作者：
J. Mandel
中科院分区：
文献类型：
--
作者：
C. Oudet;E. Mornet;J. Serre;F. Thomas;S. Lentes;C. Kretz;C. Deluchat;I. Tejada;J. Boué;A. Boué;J. Mandel
为了研究脆性X综合征突变的起源，在正常和脆弱X染色体中分析了两个多态CA重复序列，一个位于突变靶点10 kb (FRAXAC2)，另一个位于突变靶点150 kb （DXS548）。与在肌强直性营养不良中观察到的相反，脆性X突变与标记位点上的单个等位基因没有很强的相关性。然而，在正常和脆弱的X染色体之间观察到等位基因和单倍型分布的显著差异，表明有限数量的主要事件可能已经在大多数现代高加索人群中脆弱的X染色体的起源。我们提出了一个假定的方案，其中大多数观察到的脆弱的x连锁单倍型可以直接或通过一个标记位点的单个事件获得，要么是一个重复单元的改变，要么是DXS548与突变靶点之间的重组。这样的创始染色体可能在高正常范围内携带了大量的CGG重复序列，由此产生了反复的多步扩增突变。
In order to investigate the origin of mutations responsible for the fragile X syndrome, two polymorphic CA repeats, one at 10 kb (FRAXAC2) and the other at 150 kb (DXS548) from the mutation target, were analyzed in normal and fragile X chromosomes. Contrary to observations made in myotonic dystrophy, fragile X mutations were not strongly associated with a single allele at the marker loci. However, significant differences in allelic and haplotypic distributions were observed between normal and fragile X chromosomes, indicating that a limited number of primary events may have been at the origin of most present-day fragile X chromosomes in Caucasian populations. We propose a putative scheme with six founder chromosomes from which most of the observed fragile X-linked haplotypes can be derived directly or by a single event at one of the marker loci, either a change of one repeat unit or a recombination between DXS548 and the mutation target. Such founder chromosomes may have carried a number of CGG repeats in an upper-normal range, from which recurrent multistep expansion mutations have arisen.
载脂蛋白 C-II 基因中 (TG)n(AG)m 微卫星等位基因频率分布。
影响因子：
4.4
作者：
Fornage,M;Chan,L;Siest,G;Boerwinkle,E
通讯作者：
Boerwinkle,E
人类9q GT多态性图谱的构建。
影响因子：
4.4
作者：
Kwiatkowski,DJ;Henske,EP;Weimer,K;Ozelius,L;Gusella,JF;Haines,J
通讯作者：
Haines,J
影响因子：
56.9
作者：
FU, YH;PIZZUTI, A;CASKEY, CT
通讯作者：
CASKEY, CT