rs1408077

chr1-207630796-A-Cchr1-207630796-A-Gchr1-207630796-A-T

Variant summary

Our verdict is Benign. Variant got -12 ACMG points: 0P and 12B. BP4_Strong BA1

The NM_000651.6(CR1):c.7457+175A>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.841 in 152,108 control chromosomes in the GnomAD database, including 54,198 homozygotes. 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 0.84 (54198 hom., cov: 31)
• Consequence: CR1 NM_000651.6 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.682

Genes affected

CR1 (HGNC:2334): (complement C3b/C4b receptor 1 (Knops blood group)) This gene is a member of the receptors of complement activation (RCA) family and is located in the 'cluster RCA' region of chromosome 1. The genome is polymorphic at this locus with allele-specific splice variants encoding different isoforms, based on the presence/absence of long homologous repeats (LHRs). The gene encodes a monomeric single-pass type I membrane glycoprotein found on erythrocytes, leukocytes, glomerular podocytes, and splenic follicular dendritic cells. The Knops blood group system is a system of antigens located on this protein. The protein mediates cellular binding to particles and immune complexes that have activated complement. Decreases in expression of this protein and/or mutations in this gene have been associated with gallbladder carcinomas, mesangiocapillary glomerulonephritis, systemic lupus erythematosus, sarcoidosis and Alzheimer's disease. Mutations in this gene have also been associated with a reduction in Plasmodium falciparum rosetting, conferring protection against severe malaria. [provided by RefSeq, May 2020]

ACMG classification

Verdict is Benign. Variant got -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.92).
• BA1: GnomAd4 highest subpopulation (AFR) allele frequency at 95% confidence interval = 0.906 is higher than 0.05.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CR1	NM_000651.6	c.7457+175A>C		intron_variant		ENST00000367049.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CR1	ENST00000367049.9	c.7457+175A>C		intron_variant		5	NM_000651.6	P1

Frequencies

GnomAD3 genomes AF: 0.841 AC: 127873 AN: 151990 Hom.: 54142 Cov.: 31

Gnomad AFR AF: 0.913

Gnomad AMI AF: 0.802

Gnomad AMR AF: 0.868

Gnomad ASJ AF: 0.812

Gnomad EAS AF: 0.661

Gnomad SAS AF: 0.904

Gnomad FIN AF: 0.809

Gnomad MID AF: 0.842

Gnomad NFE AF: 0.808

Gnomad OTH AF: 0.850

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.841 AC: 127986 AN: 152108 Hom.: 54198 Cov.: 31 AF XY: 0.843 AC XY: 62650 AN XY: 74362

Gnomad4 AFR AF: 0.913

Gnomad4 AMR AF: 0.869

Gnomad4 ASJ AF: 0.812

Gnomad4 EAS AF: 0.660

Gnomad4 SAS AF: 0.905

Gnomad4 FIN AF: 0.809

Gnomad4 NFE AF: 0.808

Gnomad4 OTH AF: 0.850

Alfa AF: 0.814 Hom.: 26271

Bravo AF: 0.848

Asia WGS AF: 0.832 AC: 2893 AN: 3478

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.92
Cadd	Benign	0.64
Dann	Benign	0.60

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.0		Details are displayed if max score is > 0.2

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

Publications

LitVar

Other links and lift over

dbSNP: rs1408077; hg19: chr1-207804141;