Johanson–Blizzard's Syndrome with a Novel UBR1 Mutation

Abstract

Johanson–Blizzard syndrome (JBS) is a rare autosomal recessive genetic disorder, characterized by exocrine pancreatic insufficiency, a distinct abnormal facial appearance and varying degrees of growth retardation. Ubiquitin protein ligase E3 component n-recognin 1 (UBR1) gene mutations are responsible for the syndrome. Here, we describe a 2-month-old female infant, who presented with oily diarrhea, facial dysmorphia, scalp defect, hearing defects, and growth impairment. Molecular genetic testing revealed a novel frameshift mutation in UBR1, c.4027_4028 del (p.Leu1343Valfs*7), which was not previously described in JBS in the literature.

Keywords

aplasia cutis - facial dysmorphia - Johanson–Blizzard's syndrome - novel variants - pancreatic insufficiency - UBR1 gene

Note

Each of the authors has approved the final version of the case report and agreed with this submission.

Publication History

Received: 30 May 2020

Accepted: 22 July 2020

Article published online:
04 September 2020

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