Santos Neide F, Secolin Rodrigo, Brandão-Almeida Iara L, Silva Marilza S, Torres Fábio R, Tsuneda Simone S, Guimarães Catarina A, Hage Simone R V, Cendes Fernando, Guerreiro Marilisa M, Lopes-Cendes Iscia
Department of Medical Genetics, University of Campinas (UNICAMP), Campinas, São Paulo, Brazil.
Am J Med Genet A. 2008 May 1;146A(9):1151-7. doi: 10.1002/ajmg.a.32270.
Polymicrogyria (PMG) is characterized by an excessive number of small and prominent brain gyri, separated by shallow sulci. Bilateral perisylvian polymicrogyria (BPP) is the most common form of PMG. Clinical signs include pseudobulbar paresis, mental retardation, and epilepsy. Familial forms of BPP have been described and a candidate locus was previously mapped to chromosome Xq28, distal do marker DXS8103. The objective of this study was to perform linkage analysis in one family segregating BPP. A total of 15 individuals, including 8 affected patients with BPP were evaluated. Family members were examined by a neurologist and subjected to magnetic resonance imaging scans. Individuals were genotyped for 18 microsatellite markers, flanking a 42.3 cM interval on ch Xq27-q28. Two-point and multipoint linkage analysis was performed using the LINKAGE package and haplotype reconstruction was performed by GENEHUNTER software. Our results showed a wide spectrum of clinical manifestations in affected individuals with BPP, ranging from normal to mild neurological abnormalities. Two-point linkage analysis yield a Zmax = 2.06 at theta = 0.00 for markers DXS1205 and DXS1227. Multipoint lod-scores indicate a candidate interval of 13 cM between markers DSXS1205 and DXS8043, on ch Xq27.2-Xq27.3. These results point to a new locus for BPP in a more centromeric location than previously reported.
多小脑回畸形（PMG）的特征是脑回小且数量过多，脑沟浅。双侧外侧裂周多小脑回畸形（BPP）是PMG最常见的形式。临床症状包括假性延髓麻痹、智力迟钝和癫痫。已经描述了BPP的家族形式，先前已将一个候选基因座定位到Xq28染色体，位于标记DXS8103的远端。本研究的目的是对一个分离BPP的家系进行连锁分析。共评估了15名个体，包括8名患有BPP的患者。家庭成员由神经科医生进行检查，并接受磁共振成像扫描。对个体进行了18个微卫星标记的基因分型，这些标记位于Xq27-q28染色体上42.3 cM的区间两侧。使用LINKAGE软件包进行两点和多点连锁分析，并通过GENEHUNTER软件进行单倍型重建。我们的结果显示，患有BPP的受影响个体临床表现范围广泛，从正常到轻度神经异常。两点连锁分析在标记DXS1205和DXS1227处，θ = 0.00时Zmax = 2.06。多点对数得分表明在Xq27.2-Xq27.3染色体上，标记DSXS1205和DXS8043之间有一个13 cM的候选区间。这些结果表明BPP有一个新的基因座，其位置比先前报道的更靠近着丝粒。
