rs113360085
Variant summary
Our verdict is Likely benign. The variant received -6 ACMG points: 0P and 6B. BP4BP6BS1
The NM_004369.4(COL6A3):c.3445C>T(p.Arg1149Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000354 in 1,614,102 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R1149Q) has been classified as Likely benign.
Frequency
Consequence
NM_004369.4 missense
Scores
Clinical Significance
Conservation
Publications
- Bethlem myopathy 1AInheritance: AD, AR, SD Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Ambry Genetics
- collagen 6-related myopathyInheritance: AD, AR Classification: DEFINITIVE Submitted by: ClinGen
- Ullrich congenital muscular dystrophy 1CInheritance: AR Classification: DEFINITIVE Submitted by: G2P
- dystonia 27Inheritance: AR Classification: STRONG, SUPPORTIVE, LIMITED, NO_KNOWN Submitted by: Illumina, Labcorp Genetics (formerly Invitae), ClinGen, Ambry Genetics, Orphanet
- Ullrich congenital muscular dystrophy 1AInheritance: AR, AD, SD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics, Genomics England PanelApp
- Bethlem myopathyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
- Ullrich congenital muscular dystrophyInheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
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ACMG classification
Our verdict: Likely_benign. The variant received -6 ACMG points.
Transcripts
RefSeq
Ensembl
Frequencies
GnomAD3 genomes AF: 0.000263 AC: 40AN: 152130Hom.: 0 Cov.: 32 show subpopulations
GnomAD2 exomes AF: 0.000187 AC: 47AN: 251266 AF XY: 0.000177 show subpopulations
GnomAD4 exome AF: 0.000364 AC: 532AN: 1461854Hom.: 0 Cov.: 32 AF XY: 0.000370 AC XY: 269AN XY: 727232 show subpopulations
Age Distribution
GnomAD4 genome AF: 0.000263 AC: 40AN: 152248Hom.: 0 Cov.: 32 AF XY: 0.000228 AC XY: 17AN XY: 74442 show subpopulations
Age Distribution
ClinVar
Submissions by phenotype
not provided Uncertain:5
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Reported in an individual with a clinical diagnosis of LGMD who also harbored a second COL6A3 variant; however, parental studies were not reported and two variants in the NEB gene were also identified (PMID: 25214167); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; This variant is associated with the following publications: (PMID: 23040494, 30564623, 25214167, 39983722) -
The COL6A3 p.Arg542Trp variant was not identified in the literature but was identified in dbSNP (ID: rs113360085) and ClinVar (classified as uncertain significance by EGL Genetic Diagnostics, GeneDx, and Invitae, and as likely benign by Illumina). The variant was identified in control databases in 56 of 282644 chromosomes at a frequency of 0.0001981 (Genome Aggregation Database March 6, 2019, v2.1.1). The variant was observed in the following populations: European (non-Finnish) in 45 of 129010 chromosomes (freq: 0.000349) and Latino in 11 of 35436 chromosomes (freq: 0.00031), but was not observed in the African, Ashkenazi Jewish, East Asian, European (Finnish), Other, or South Asian populations. The p.Arg542 residue is not conserved in mammals and computational analyses (PolyPhen-2, SIFT, AlignGVGD, BLOSUM, MutationTaster) provide inconsistent predictions regarding the impact to the protein; this information is not very predictive of pathogenicity. The variant occurs outside of the splicing consensus sequence and in silico or computational prediction software programs (SpliceSiteFinder, MaxEntScan, NNSPLICE, GeneSplicer) do not predict a difference in splicing. In summary, based on the above information the clinical significance of this variant cannot be determined with certainty at this time. This variant is classified as a variant of uncertain significance. -
not specified Uncertain:1
Variant summary: COL6A3 c.3445C>T (p.Arg1149Trp) results in a non-conservative amino acid change located in the von Willebrand factor (vWF) type A domain (IPR002035) of the encoded protein sequence. Four of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 0.00019 in 251266 control chromosomes. This frequency is not significantly higher than estimated for a pathogenic variant in COL6A3 causing Ullrich congenital muscular dystrophy 1-AR (0.00019 vs 0.0035), allowing no conclusion about variant significance. c.3445C>T has been reported in the literature in at least one compound heterozygous individual affected with Limb-girdle muscular dystrophy carrying a second variant classified as benign in the presence of additional variants in the NEB gene (e.g. Savarese_2014). This report does not provide unequivocal conclusions about association of the variant with Ullrich congenital muscular dystrophy 1-AR. To our knowledge, no experimental evidence demonstrating an impact on protein function has been reported. The following publication has been ascertained in the context of this evaluation (PMID: 25214167). ClinVar contains an entry for this variant (Variation ID: 284774). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Bethlem myopathy 1A Benign:1
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Collagen 6-related myopathy Benign:1
This variant was observed as part of a predisposition screen in an ostensibly healthy population. A literature search was performed for the gene, cDNA change, and amino acid change (where applicable). Publications were found based on this search. The evidence from the literature, in combination with allele frequency data from public databases where available, was sufficient to determine this variant is unlikely to cause disease. Therefore, this variant is classified as likely benign. -
Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at