B9D1 is revealed as a novel Meckel syndrome (MKS) gene by targeted exon-enriched next-generation sequencing and deletion analysis
B9D1 is revealed as a novel Meckel syndrome (MKS) gene by targeted exon-enriched next-generation sequencing and deletion analysis
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DOI：
10.1093/hmg/ddr151
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发表时间：
2011-07-01
影响因子：
3.5
通讯作者：
Harris, Peter C.
中科院分区：
文献类型：
--
作者：
Hopp, Katharina;Heyer, Christina M.;Harris, Peter C.
Meckel综合征(MKS)是一种胚胎致死性常染色体隐性遗传病，以多囊肾病、中枢神经系统缺陷、多指和肝纤维化为特征。这种疾病被认为与初级纤毛的缺陷有关；因此，它被归类为纤毛病。到目前为止，与MKS相关的基因有6个(MKS1、TMEM67、TMEM216、CEP290、CC2D2A和RPGRIP1L)。然而，对这些基因的突变筛查显示，在我们的MKS队列(46个家庭)中，只有略多于一半的人有两个突变的等位基因，这表明遗传异质性水平更高。为了探索MKS的全部遗传复杂性，我们使用RainDance微滴-PCR富集法和IllLumaGAIIx下一代测序技术对12个MKS家系的31个纤毛疾病基因进行了外显子丰富的下一代测序。在M456家族中，我们检测到一个新的MKS基因B9D1的剪接供体位点发生了变化。B9D1蛋白在结构上与MKS1相似，已被证明在秀丽线虫纤毛发生中起重要作用。逆转录聚合酶链式反应显示，B9D1基因外显子4不存在移码突变，仅有一个较小的基因产物。arrayCGH显示，第二个突变是1.713 Mb的从头缺失，完全删除了B9D1等位基因。免疫荧光分析显示，与对照组相比，患者纤毛细胞水平显著降低，证实了B9D1在纤毛发生中的作用。胎儿遗传了第二个MKS基因CEP290；p.R2210C的另一个可能致病的新错义改变，提示这种疾病的遗传是寡基因遗传。
Meckel syndrome (MKS) is an embryonic lethal, autosomal recessive disorder characterized by polycystic kidney disease, central nervous system defects, polydactyly and liver fibrosis. This disorder is thought to be associated with defects in primary cilia; therefore, it is classed as a ciliopathy. To date, six genes have been commonly associated with MKS (MKS1, TMEM67, TMEM216, CEP290, CC2D2A and RPGRIP1L). However, mutation screening of these genes revealed two mutated alleles in only just over half of our MKS cohort (46 families), suggesting an even greater level of genetic heterogeneity. To explore the full genetic complexity of MKS, we performed exon-enriched next-generation sequencing of 31 ciliopathy genes in 12 MKS pedigrees using RainDance microdroplet-PCR enrichment and IlluminaGAIIx next-generation sequencing. In family M456, we detected a splice-donor site change in a novel MKS gene, B9D1. The B9D1 protein is structurally similar to MKS1 and has been shown to be of importance for ciliogenesis in Caenorhabditis elegans. Reverse transcriptase-PCR analysis of fetal RNA revealed, hemizygously, a single smaller mRNA product with a frameshifting exclusion of B9D1 exon 4. ArrayCGH showed that the second mutation was a 1.713 Mb de novo deletion completely deleting the B9D1 allele. Immunofluorescence analysis highlighted a significantly lower level of ciliated patient cells compared to controls, confirming a role for B9D1 in ciliogenesis. The fetus inherited an additional likely pathogenic novel missense change to a second MKS gene, CEP290; p.R2210C, suggesting oligogenic inheritance in this disorder.