chr15-27985106-T-C
Variant summary
Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1PM2PP3_StrongPP5
The NM_000275.3(OCA2):āc.1322A>Gā(p.Asp441Gly) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000124 in 1,613,858 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).
Frequency
Consequence
NM_000275.3 missense
Scores
Clinical Significance
Conservation
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ACMG classification
Verdict is Likely_pathogenic. Variant got 9 ACMG points.
Transcripts
RefSeq
Ensembl
Gene | Transcript | HGVSc | HGVSp | Effect | Exon rank | TSL | MANE | Protein | Appris | UniProt |
---|---|---|---|---|---|---|---|---|---|---|
OCA2 | ENST00000354638.8 | c.1322A>G | p.Asp441Gly | missense_variant | Exon 13 of 24 | 1 | NM_000275.3 | ENSP00000346659.3 | ||
OCA2 | ENST00000353809.9 | c.1250A>G | p.Asp417Gly | missense_variant | Exon 12 of 23 | 1 | ENSP00000261276.8 |
Frequencies
GnomAD3 genomes AF: 0.00000657 AC: 1AN: 152130Hom.: 0 Cov.: 32
GnomAD3 exomes AF: 0.00000800 AC: 2AN: 250048Hom.: 0 AF XY: 0.00000739 AC XY: 1AN XY: 135288
GnomAD4 exome AF: 6.84e-7 AC: 1AN: 1461728Hom.: 0 Cov.: 34 AF XY: 0.00000138 AC XY: 1AN XY: 727148
GnomAD4 genome AF: 0.00000657 AC: 1AN: 152130Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0AN XY: 74316
ClinVar
Submissions by phenotype
not provided Pathogenic:1Uncertain:2
Observed in a patient in published literature with oculocutaneous albinism (Shahzad et al., 2017), although it is not stated whether this variant was present in the homozygous or heterozygous state; In silico analysis, which includes protein predictors and evolutionary conservation, supports a deleterious effect; This variant is associated with the following publications: (PMID: 28266639) -
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This sequence change replaces aspartic acid, which is acidic and polar, with glycine, which is neutral and non-polar, at codon 441 of the OCA2 protein (p.Asp441Gly). This variant is present in population databases (rs147816326, gnomAD 0.004%). This missense change has been observed in individual(s) with clinical features of oculocutaneous albinism (PMID: 28266639; internal data). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 502704). Invitae Evidence Modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) indicates that this missense variant is expected to disrupt OCA2 protein function with a positive predictive value of 80%. Experimental studies have shown that this missense change affects OCA2 function (PMID: 28266639). This variant disrupts the p.Asp441 amino acid residue in OCA2. Other variant(s) that disrupt this residue have been determined to be pathogenic (internal data). This suggests that this residue is clinically significant, and that variants that disrupt this residue are likely to be disease-causing. For these reasons, this variant has been classified as Pathogenic. -
SKIN/HAIR/EYE PIGMENTATION 1, BLUE/NONBLUE EYES Pathogenic:1
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Nonsyndromic Oculocutaneous Albinism Pathogenic:1
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not specified Uncertain:1
Variant summary: OCA2 c.1322A>G (p.Asp441Gly) results in a non-conservative amino acid change located in the citrate transporter-like domain (IPR004680) of the encoded protein sequence. Five of five in-silico tools predict a damaging effect of the variant on protein function. The variant allele was found at a frequency of 8e-06 in 250048 control chromosomes (gnomAD). The available data on variant occurrences in the general population are insufficient to allow any conclusion about variant significance. c.1322A>G has been reported in the literature as an uninformative genotype (i.e. zygosity not specified) in at least one affected individual from a family with with Oculocutaneous Albinism (Shahzad_2017). This report does not provide unequivocal conclusions about association of the variant with Oculocutaneous Albinism. 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: 28266639). Five submitters have provided clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as either VUS (n=3) or likely pathogenic (n=2). Based on the evidence outlined above, the variant was classified as uncertain significance. -
Tyrosinase-positive oculocutaneous albinism Uncertain:1
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Computational scores
Source:
Splicing
Find out detailed SpliceAI scores and Pangolin per-transcript scores at