Unidade de Genética, Instituto da Criança, Hospital das Clínicas da FMUSP, Universidade de São Paulo, São Paulo, Brazil.
Instituto Biociências, Universidade de São Paulo, São Paulo, Brazil.
Clin Genet. 2018 Apr;93(4):800-811. doi: 10.1111/cge.13169. Epub 2018 Feb 20.
Richieri-Costa-Pereira syndrome is a rare autosomal recessive acrofacial dysostosis that has been mainly described in Brazilian individuals. The cardinal features include Robin sequence, cleft mandible, laryngeal anomalies and limb defects. A biallelic expansion of a complex repeated motif in the 5' untranslated region of EIF4A3 has been shown to cause this syndrome, commonly with 15 or 16 repeats. The only patient with mild clinical findings harbored a 14-repeat expansion in 1 allele and a point mutation in the other allele. This proband is described here in more details, as well as is his affected sister, and 5 new individuals with Richieri-Costa-Pereira syndrome, including a patient from England, of African ancestry. This study has expanded the phenotype in this syndrome by the observation of microcephaly, better characterization of skeletal abnormalities, less severe phenotype with only mild facial dysmorphisms and limb anomalies, as well as the absence of cleft mandible, which is a hallmark of the syndrome. Although the most frequent mutation in this study was the recurrent 16-repeat expansion in EIF4A3, there was an overrepresentation of the 14-repeat expansion, with mild phenotypic expression, thus suggesting that the number of these motifs could play a role in phenotypic delineation.
里谢里-科斯塔-佩雷拉综合征是一种罕见的常染色体隐性颅面发育不良疾病,主要见于巴西人。其主要特征包括罗宾序列、下颌裂、喉部异常和肢体缺陷。已经表明,EIF4A3 的 5'非翻译区中复杂重复基序的双等位基因扩展会导致这种综合征,通常有 15 或 16 个重复。唯一一位临床表型较轻的患者在 1 个等位基因中携带 14 个重复扩展,而另一个等位基因中存在点突变。本文详细描述了该先证者及其受累的妹妹,以及 5 名新的里谢里-科斯塔-佩雷拉综合征患者,包括一名来自英国的非洲裔患者。通过观察发现该综合征的表型扩展为小颅畸形,骨骼异常特征更好,面部畸形和肢体异常较轻,下颌裂缺失,这些都是该综合征的特征。虽然本研究中最常见的突变是 EIF4A3 中反复出现的 16 个重复扩展,但 14 个重复扩展的发生率过高,且表型表达较轻,这表明这些重复基序的数量可能在表型描绘中起作用。