2-203871488-G-T

Variant names:

• chr2-203871488-G-T
• rs1553657487
• NM_005214.5:c.567+1G>T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_005214.5(CTLA4):​c.567+1G>T variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.000000687 in 1,455,018 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: 6.9e-7 (0 hom.)
• Consequence: CTLA4 NM_005214.5 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.34
• Publications: 0 publications found

Genes affected

CTLA4 (HGNC:2505): (cytotoxic T-lymphocyte associated protein 4) This gene is a member of the immunoglobulin superfamily and encodes a protein which transmits an inhibitory signal to T cells. The protein contains a V domain, a transmembrane domain, and a cytoplasmic tail. Alternate transcriptional splice variants, encoding different isoforms, have been characterized. The membrane-bound isoform functions as a homodimer interconnected by a disulfide bond, while the soluble isoform functions as a monomer. Mutations in this gene have been associated with insulin-dependent diabetes mellitus, Graves disease, Hashimoto thyroiditis, celiac disease, systemic lupus erythematosus, thyroid-associated orbitopathy, and other autoimmune diseases. [provided by RefSeq, Jul 2008]

CTLA4 Gene-Disease associations (from GenCC):

• autoimmune lymphoproliferative syndrome due to CTLA4 haploinsufficiency

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet
• systemic lupus erythematosus

  Inheritance: Unknown Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005214.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CTLA4	NM_005214.5	MANE Select	c.567+1G>T		splice_donor intron	N/A	NP_005205.2
	CTLA4	NM_001037631.3		c.457+555G>T		intron	N/A	NP_001032720.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CTLA4	ENST00000648405.2	MANE Select	c.567+1G>T		splice_donor intron	N/A	ENSP00000497102.1
	CTLA4	ENST00000487393.1	TSL:1	c.110-1220G>T		intron	N/A	ENSP00000497319.1
	CTLA4	ENST00000696479.1		c.639+1G>T		splice_donor intron	N/A	ENSP00000512655.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.87e-7 AC: 1 AN: 1455018 Hom.: 0 Cov.: 29 AF XY: 0.00 AC XY: 0 AN XY: 724446

African (AFR) AF: 0.00 AC: 0 AN: 33326

American (AMR) AF: 0.00 AC: 0 AN: 44706

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26092

East Asian (EAS) AF: 0.00 AC: 0 AN: 39654

South Asian (SAS) AF: 0.00 AC: 0 AN: 86122

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53414

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5704

European-Non Finnish (NFE) AF: 9.04e-7 AC: 1 AN: 1105862

Other (OTH) AF: 0.00 AC: 0 AN: 60138

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	0.15
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Uncertain	0.88	D
PhyloP100		6.3
GERP RS		5.2
Mutation Taster		=26/74	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.96		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.96		Position offset: -1

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

Other links and lift over

dbSNP: rs1553657487; hg19: chr2-204736211;