A rare case of spondyloepimetaphyseal dysplasia with joint laxity, type 3 (EXOC6B gene) (SEMDJL3)
DOI:
https://doi.org/10.18203/2349-3291.ijcp20261924Keywords:
Spondyloepimetaphyseal dysplasia with joint laxity type 3, Ultra rare, EXOC6B geneAbstract
Spondyloepimetaphyseal dysplasia with joint laxity, type 3 (SEMDJL3) is an ultra-rare condition, inherited in autosomal recessive manner caused by mutations in EXOC6B gene, encoding a component of the exocyst complex, crucial for cell growth and exocytosis. It is characterized by multiple joint dislocations, joint laxity, genu valgum, short stature, and skeletal dysplasia. There are approximately 6 confirmed cases reported worldwide and only one or two cases in India. Patient presented with complain of not gaining height and was later diagnosed with SEMDJL3.This case review aims to increase awareness of this rare disorder, which remains underdiagnosed due to the scarcity of documented cases and some overlap with other syndromes.
References
Simsek-Kiper PO, Jacob P, Upadhyai P, Taşkıran ZE, Guleria VS, Karaosmanoglu B, et al. Biallelic loss-of-function variants in EXOC6B are associated with impaired primary ciliogenesis and cause spondylo-epi-metaphyseal dysplasia with joint laxity type 3. Human Mutation. 2022;43:2116-29.
Bhavani GS, Singh S, Girisha KM. EXOC6B-Related spondyloepimetaphyseal dysplasia with joint laxity. In: Adam MP, Bick S, Mirzaa GM, Pagon RA, Wallace SE, Amemiya A, editors. GeneReviews®. Seattle (WA): University of Washington, Seattle; 1993–2026. 2023.
Beighton P, Gericke G, Kozlowski K, Grobler L. The manifestations and natural history of spondylo-epi-metaphyseal dysplasia with joint laxity. Clin Genet. 1984;26(4):308-17.
Campos-Xavier B, Rogers RC, Niel-Bütschi F, Ferreira C, Unger S, Spranger J, et al. Confirmation of spondylo-epi-metaphyseal dysplasia with joint laxity, EXOC6B type. Am J Med Genet A. 2018;176(12):2934-5.
Hall JG. Spondyloepimetaphyseal dysplasia with joint laxity. J Med Genet. 1971;8(4):358-61.