chr15-27951844-C-T

Variant names:

• chr15-27951844-C-T
• rs1555440003
• NM_000275.3:c.1891G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM1 PM2 PP3_Strong

The NM_000275.3(OCA2):​c.1891G>A​(p.Gly631Arg) variant causes a missense change. The variant allele was found at a frequency of 0.00000248 in 1,613,920 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 Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G631A) has been classified as Uncertain significance.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: OCA2 NM_000275.3 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: 4.41
• Publications: 0 publications found

Genes affected

OCA2 (HGNC:8101): (OCA2 melanosomal transmembrane protein) This gene encodes the human homolog of the mouse p (pink-eyed dilution) gene. The encoded protein is believed to be an integral membrane protein involved in small molecule transport, specifically tyrosine, which is a precursor to melanin synthesis. It is involved in mammalian pigmentation, where it may control skin color variation and act as a determinant of brown or blue eye color. Mutations in this gene result in type 2 oculocutaneous albinism. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2014]

OCA2 Gene-Disease associations (from GenCC):

• oculocutaneous albinism type 2

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Orphanet, G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 ACMG points.

• PM1: In a hotspot region, there are 3 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 7 uncertain in NM_000275.3
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.984

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000275.3. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OCA2	NM_000275.3	MANE Select	c.1891G>A	p.Gly631Arg	missense	Exon 18 of 24	NP_000266.2	Q04671-1
	OCA2	NM_001300984.2		c.1819G>A	p.Gly607Arg	missense	Exon 17 of 23	NP_001287913.1	Q04671-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	OCA2	ENST00000354638.8	TSL:1 MANE Select	c.1891G>A	p.Gly631Arg	missense	Exon 18 of 24	ENSP00000346659.3	Q04671-1
	OCA2	ENST00000353809.9	TSL:1	c.1819G>A	p.Gly607Arg	missense	Exon 17 of 23	ENSP00000261276.8	Q04671-2
	OCA2	ENST00000910120.1		c.1891G>A	p.Gly631Arg	missense	Exon 18 of 26	ENSP00000580179.1

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152132 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461788 Hom.: 0 Cov.: 31 AF XY: 0.00000275 AC XY: 2 AN XY: 727208

African (AFR) AF: 0.0000597 AC: 2 AN: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.00 AC: 0 AN: 86244

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111934

Other (OTH) AF: 0.0000166 AC: 1 AN: 60390

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152132 Hom.: 0 Cov.: 33 AF XY: 0.0000135 AC XY: 1 AN XY: 74320

African (AFR) AF: 0.0000241 AC: 1 AN: 41426

American (AMR) AF: 0.00 AC: 0 AN: 15264

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5192

South Asian (SAS) AF: 0.00 AC: 0 AN: 4810

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10620

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68028

Other (OTH) AF: 0.00 AC: 0 AN: 2092

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
-	1	-	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.89
BayesDel_addAF	Pathogenic	0.41	D
BayesDel_noAF	Pathogenic	0.35
CADD	Uncertain	24
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.90	D
Eigen	Uncertain	0.64
Eigen_PC	Uncertain	0.59
FATHMM_MKL	Uncertain	0.93	D
LIST_S2	Uncertain	0.94	D
M_CAP	Uncertain	0.14	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	0.84	D
MutationAssessor	Pathogenic	3.1	M
PhyloP100		4.4
PrimateAI	Benign	0.44	T
PROVEAN	Uncertain	-3.0	D
REVEL	Pathogenic	0.87
Sift	Benign	0.14	T
Sift4G	Benign	0.28	T
Polyphen		0.94	P
Vest4		0.86
MutPred		0.91		Gain of methylation at G631 (P = 0.0053)
MVP		1.0
MPC		0.47
ClinPred		0.94	D
GERP RS		5.2
Varity_R		0.31
gMVP		0.89

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.080		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1555440003; hg19: chr15-28196990;