chr6-31271305-G-T

Variant names:

• chr6-31271305-G-T
• rs1050384
• NM_002117.6:c.387C>A

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PM2

The NM_002117.6(HLA-C):​c.387C>A​(p.Pro129Pro) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000498 in 1,004,792 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.0 (0 hom., cov: 6)
  • Exomes 𝑓: 0.0000050 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: HLA-C NM_002117.6 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -6.48
• Publications: 13 publications found

Genes affected

HLA-C (HGNC:4933): (major histocompatibility complex, class I, C) HLA-C belongs to the HLA class I heavy chain paralogues. This class I molecule is a heterodimer consisting of a heavy chain and a light chain (beta-2 microglobulin). The heavy chain is anchored in the membrane. Class I molecules play a central role in the immune system by presenting peptides derived from endoplasmic reticulum lumen. They are expressed in nearly all cells. The heavy chain is approximately 45 kDa and its gene contains 8 exons. Exon one encodes the leader peptide, exons 2 and 3 encode the alpha1 and alpha2 domain, which both bind the peptide, exon 4 encodes the alpha3 domain, exon 5 encodes the transmembrane region, and exons 6 and 7 encode the cytoplasmic tail. Polymorphisms within exon 2 and exon 3 are responsible for the peptide binding specificity of each class one molecule. Typing for these polymorphisms is routinely done for bone marrow and kidney transplantation. About 6000 HLA-C alleles have been described. The HLA system plays an important role in the occurrence and outcome of infectious diseases, including those caused by the malaria parasite, the human immunodeficiency virus (HIV), and the severe acute respiratory syndrome coronavirus (SARS-CoV). The structural spike and the nucleocapsid proteins of the novel coronavirus SARS-CoV-2, which causes coronavirus disease 2019 (COVID-19), are reported to contain multiple Class I epitopes with predicted HLA restrictions. Individual HLA genetic variation may help explain different immune responses to a virus across a population.[provided by RefSeq, Aug 2020]

ENSG00000298396 (HGNC:):

ACMG classification

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HLA-C	NM_002117.6	c.387C>A	p.Pro129Pro	synonymous_variant	Exon 3 of 8	ENST00000376228.10	NP_002108.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HLA-C	ENST00000376228.10	c.387C>A	p.Pro129Pro	synonymous_variant	Exon 3 of 8	6	NM_002117.6	ENSP00000365402.5

Frequencies

GnomAD3 genomes AF: 0.00 AC: 0 AN: 62928 Hom.: 0 Cov.: 6

Gnomad AFR AF: 0.00

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: 0.00000498 AC: 5 AN: 1004792 Hom.: 0 Cov.: 28 AF XY: 0.00000396 AC XY: 2 AN XY: 504670

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 19888

American (AMR) AF: 0.00 AC: 0 AN: 28678

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 14898

East Asian (EAS) AF: 0.00 AC: 0 AN: 23354

South Asian (SAS) AF: 0.0000152 AC: 1 AN: 65654

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 31882

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 3082

European-Non Finnish (NFE) AF: 0.00000515 AC: 4 AN: 776516

Other (OTH) AF: 0.00 AC: 0 AN: 40840

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 62928 Hom.: 0 Cov.: 6 AF XY: 0.00 AC XY: 0 AN XY: 30000

African (AFR) AF: 0.00 AC: 0 AN: 12998

American (AMR) AF: 0.00 AC: 0 AN: 5710

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 892

East Asian (EAS) AF: 0.00 AC: 0 AN: 1688

South Asian (SAS) AF: 0.00 AC: 0 AN: 1702

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 4336

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 100

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 34276

Other (OTH) AF: 0.00 AC: 0 AN: 756

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.95
CADD	Benign	17
DANN	Benign	0.79
PhyloP100		-6.5
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.38		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.38		Position offset: -2

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

Other links and lift over

dbSNP: rs1050384; hg19: chr6-31239082;