1-207470103-G-T

Variant names:

• chr1-207470103-G-T
• rs398122864
• NM_001006658.3:c.1225+1G>T

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Strong PM2

The NM_001006658.3(CR2):​c.1225+1G>T variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.000000684 in 1,461,154 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CR2 NM_001006658.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.09
• Publications: 0 publications found

Genes affected

CR2 (HGNC:2336): (complement C3d receptor 2) This gene encodes a membrane protein, which functions as a receptor for Epstein-Barr virus (EBV) binding on B and T lymphocytes. Genetic variations in this gene are associated with susceptibility to systemic lupus erythematosus type 9 (SLEB9). Alternatively spliced transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Sep 2009]

CR2 Gene-Disease associations (from GenCC):

• immunodeficiency, common variable, 7

  Inheritance: AR Classification: DEFINITIVE, STRONG, MODERATE Submitted by: ClinGen, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• common variable immunodeficiency

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• systemic lupus erythematosus

  Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.12442818 fraction of the gene. Cryptic splice site detected, with MaxEntScore 3.4, offset of 12, new splice context is: ccgGTactc. Cryptic site results in inframe change. If cryptic site found is not functional and variant results in exon loss, it results in inframe change.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001006658.3. 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
	CR2	NM_001006658.3	MANE Select	c.1225+1G>T		splice_donor intron	N/A	NP_001006659.1	P20023-3
	CR2	NM_001877.5		c.1225+1G>T		splice_donor intron	N/A	NP_001868.2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CR2	ENST00000367057.8	TSL:1 MANE Select	c.1225+1G>T		splice_donor intron	N/A	ENSP00000356024.3	P20023-3
	CR2	ENST00000367058.7	TSL:1	c.1225+1G>T		splice_donor intron	N/A	ENSP00000356025.3	P20023-1
	CR2	ENST00000367059.3	TSL:1	c.1225+1G>T		splice_donor intron	N/A	ENSP00000356026.3	Q5SR47

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461154 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 726896

African (AFR) AF: 0.00 AC: 0 AN: 33434

American (AMR) AF: 0.00 AC: 0 AN: 44680

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26126

East Asian (EAS) AF: 0.00 AC: 0 AN: 39690

South Asian (SAS) AF: 0.00 AC: 0 AN: 86230

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53380

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5478

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111800

Other (OTH) AF: 0.00 AC: 0 AN: 60336

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.60	D
BayesDel_noAF	Pathogenic	0.23
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.83
FATHMM_MKL	Uncertain	0.93	D
PhyloP100		4.1
Mutation Taster		=1/99	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.98		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.20		Position offset: 24
DS_DL_spliceai		0.98		Position offset: -1

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

dbSNP: rs398122864;

hg19: chr1-207643448;