Novel SCN9A variant associated with congenital insensitivity to pain
Tony Yammine1, Raffi Aprahamian1, Mirna Souaid1
1Medical Genetics Unit, Saint Joseph University, B.P.17-5208, Mar Mikhael, Beirut, 11042020, Lebanon.
Background:
Congenital insensitivity to pain (CIP) is a rare autosomal recessive syndrome characterized by lack of pain perception and a wide spectrum of clinical signs such as anosmia and hyposmia. Variants in SCN9A gene are associated with CIP. We here report on a Lebanese family with three CIP patients referred for genetic investigations.
Methods And Results:
Whole exome sequencing analysis revealed the presence of a novel nonsense, homozygous SCN9A pathogenic variant: SCN9A (NM_001365536.1): c.4633G > T, p.(Glu1545*) in exon 26.
Conclusion:
Our three Lebanese patients had CIP, urinary incontinence and normal olfactory function while two of them also presented with osteoporosis and osteoarthritis; this association of features has not been previously reported in the literature. We hope that this report would contribute to a better delineation of the phenotypic spectrum associated with SCN9A pathogenic variants.
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