Patients with deletion of chromosome 13 present with variable clinical features, and the correlation between phenotype and genomic aberration is not well established in the literature, mainly due to variable sizes of the deleted segments and inaccuracy of breakpoint mapping. In order to improve the genotype-phenotype correlation, we obtained clinical and cytogenomic data from 5 Brazilian patients with different chromosome 13 deletions characterized by G-banding and array techniques. Breakpoints were nonrecurrent, with deletion sizes ranging from 3.8 to 43.3 Mb. Our patients showed some classic features associated with 13q deletion, independent of the location and size of the deletion: hypotonia, growth delay, psychomotor developmental delay, microcephaly, central nervous system anomalies, and minor facial dysmorphism as well as urogenital and limb abnormalities. Comparisons between the literature and our patients' data allowed us to narrow the critical regions that were previously reported for microphthalmia and urogenital abnormalities, indicating that gene haploinsufficiency of ARHGEF7, PCDH9 and DIAPH3, of MIR17HG and GPC6, and of EFNB2 may contribute to microcephaly, cardiovascular disease, and urogenital abnormalities, respectively. The knowledge about genes involved in the phenotypic features found in 13q deletion patients may help us to understand how the genes interact and contribute to their clinical phenotype, improving the patient's clinical follow-up.

中文翻译：

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由于不同的重排和对表型的影响，第13号染色体的删除。

具有13号染色体缺失的患者表现出可变的临床特征，并且在表型和基因组畸变之间的相关性在文献中尚未得到很好的建立，这主要是由于缺失区段的可变大小和断点图的不准确性所致。为了改善基因型与表型的相关性，我们从5名巴西患者中获得了临床和细胞基因组学数据，这些患者具有13条染色体的不同缺失，这些患者均具有G谱带和阵列技术。断点是非周期性的，删除大小范围为3.8至43.3 Mb。我们的患者显示出与13q缺失相关的一些经典特征，而与缺失的位置和大小无关：肌张力减退，生长延迟，精神运动发育延迟，小头畸形，中枢神经系统异常，以及轻微的面部畸形以及泌尿生殖器和四肢异常。文献和患者数据之间的比较使我们能够缩小先前报道的小眼病和泌尿生殖道异常的关键区域，这表明ARHGEF7，PCDH9和DIAPH3，MIR17HG和GPC6以及EFNB2的基因单倍性不足可能会导致小头畸形，心血管疾病和泌尿生殖器异常。有关在13q缺失患者中发现的涉及表型特征的基因的知识，可以帮助我们了解基因如何相互作用并促进其临床表型，从而改善患者的临床随访。数据使我们能够缩小先前报道的小眼病和泌尿生殖道异常的关键区域，这表明ARHGEF7，PCDH9和DIAPH3，MIR17HG和GPC6以及EFNB2的基因单倍不足可能分别导致小头畸形，心血管疾病和泌尿生殖道异常。有关在13q缺失患者中发现的涉及表型特征的基因的知识，可以帮助我们了解基因如何相互作用并促进其临床表型，从而改善患者的临床随访。数据使我们能够缩小先前报道的小眼病和泌尿生殖道异常的关键区域，这表明ARHGEF7，PCDH9和DIAPH3，MIR17HG和GPC6以及EFNB2的基因单倍不足可能分别导致小头畸形，心血管疾病和泌尿生殖道异常。有关在13q缺失患者中发现的涉及表型特征的基因的知识，可以帮助我们了解基因如何相互作用并促进其临床表型，从而改善患者的临床随访。