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Spondyloepimetaphysial Dysplasia with Joint Laxity in Three Siblings with B3GALT6 Mutations
Pamela Trejo1, Frank Rauch1, Francis H Glorieux1
1Shriners Hospital for Children and McGill University, Department of Pediatrics, CHU Sainte-Justine Hospital, University of Montreal, Montreal, Québec, Canada.
Abstract:
Spondyloepimetaphyseal dysplasia with joint laxity type 1 (SEMDJL1) is a rare entity with a recessive inheritance. In this report, we describe 3 affected members of the same family who present with short stature, hyperlaxity with secondary spinal malalignment, ulnar subluxation, developmental dysplasia of the hips, and craniofacial alterations; one member also had learning difficulties. DNA analysis showed compound heterozygous variants in the B3GALT6 gene (c.901_921dup, c.511C>T) in all 3 patients, inherited from the parents. This family demonstrates the clinical variability of SEMDJL1.
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