Identification of a novel de novo mutation in the NIPBL gene in an Iranian patient with Cornelia de Lange syndrome: A case report

Abstract

Background: Cornelia de Lange syndrome is characterized by dysmorphic facial features, hirsutism, severe growth and developmental delay. Germline mutations in the NIPBL gene with an autosomal dominant pattern and in the SMC1A gene with an X-linked pattern have been identified in Cornelia de Lange syndrome.

Case presentation: A two-month-old Iranian boy who showed multiple congenital anomalies was referred to the genetic center of a welfare organization in southwest Iran. He was the second child of a non-consanguineous marriage, born after full term with normal delivery. His birth weight was 3110 g, his length was 46 cm and his head circumference was 30 cm. Both parents were clinically asymptomatic, with no positive history of any deformity in their respective families.

Conclusions: Sequencing of the NIPBL gene from our patient revealed a single-base deletion of thymidine in exon 10 (c.516delT). This mutation presumably results in premature termination at codon 526. We did not observe this mutation in the parents of our patient with Cornelia de Lange syndrome. The results presented here enlarge the spectrum of NIPBL gene mutations associated with Cornelia de Lange syndrome by identifying a novel de novo mutation in an Iranian patient with Cornelia de Lange syndrome and further support the hypothesis that NIPBL mutations are disease-causing mutations leading to Cornelia de Lange syndrome.

Figure 1

Characteristic features of Cornelia de Lange syndrome. (A) Hirsutism. (B,C) Variability of upper-limb abnormalities (distal reduction defect with missing and fused digits in the same child).

Figure 2

Sequencing of the NIPBL gene. (A) Chromograph from the affected individual showing a heterozygous deletion of a thymidine (-T) at codon 516 (black arrow). (B) Chromograph from a healthy individual with a wild-type sequence. Letters between both chromographs indicate the partial cDNA sequence of the NIPBL gene with corresponding codons beginning with codon 511.