ClinVar

Description

The p.T351S variant (also known as c.1052C>G), located in coding exon 8 of the CFTR gene, results from a C to G substitution at nucleotide position 1052. The threonine at codon 351 is replaced by serine, an amino acid with similar properties. This variant has been reported in trans with a disease-causing mutation in an unaffected father of a cystic fibrosis patient (Mercier B et al. Hum. Mutat., 1993;2:16-20) as well as in an individual with diffuse bronchiectasis and normal sweat chloride levels (Bienvenu T et al. Am. J. Respir. Crit. Care Med., 2010 May;181:1078-84). This alteration was reported to be homozygous (and in cis with a second variant on both alleles) in a patient with a CFTR-related disorder (Trujillano et al. J Med Genet. 2013;50(7):455-62). Another study described this variant to be in cis with p.F508del in a patient with features of cystic fibrosis; a second disease causing alteration was not reported (Dal'Maso et al. J Bras Pneumol. 2013;39(2):181-9). This amino acid position is highly conserved in available vertebrate species. In addition, the in silico prediction for this alteration is inconclusive. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.