17-44251588-C-T

Variant names:

• chr17-44251588-C-T
• rs121912741
• NM_000342.4:c.2312G>A

Variant summary

Our verdict is Likely pathogenic. The variant received 9 ACMG points: 9P and 0B. PM1 PM2 PM5 PP3 PP5_Moderate

The NM_000342.4(SLC4A1):​c.2312G>A​(p.Gly771Asp) variant causes a missense, splice region change. The variant allele was found at a frequency of 0.00000657 in 152,126 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 2/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G771V) has been classified as Likely pathogenic.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: SLC4A1 NM_000342.4 missense, splice_region
• Scores: Splicing: ADA: 0.9996
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 6.07
• Publications: 5 publications found

Genes affected

SLC4A1 (HGNC:11027): (solute carrier family 4 member 1 (Diego blood group)) The protein encoded by this gene is part of the anion exchanger (AE) family and is expressed in the erythrocyte plasma membrane, where it functions as a chloride/bicarbonate exchanger involved in carbon dioxide transport from tissues to lungs. The protein comprises two domains that are structurally and functionally distinct. The N-terminal 40kDa domain is located in the cytoplasm and acts as an attachment site for the red cell skeleton by binding ankyrin. The glycosylated C-terminal membrane-associated domain contains 12-14 membrane spanning segments and carries out the stilbene disulphonate-sensitive exchange transport of anions. The cytoplasmic tail at the extreme C-terminus of the membrane domain binds carbonic anhydrase II. The encoded protein associates with the red cell membrane protein glycophorin A and this association promotes the correct folding and translocation of the exchanger. This protein is predominantly dimeric but forms tetramers in the presence of ankyrin. Many mutations in this gene are known in man, and these mutations can lead to two types of disease: destabilization of red cell membrane leading to hereditary spherocytosis, and defective kidney acid secretion leading to distal renal tubular acidosis. Other mutations that do not give rise to disease result in novel blood group antigens, which form the Diego blood group system. Southeast Asian ovalocytosis (SAO, Melanesian ovalocytosis) results from the heterozygous presence of a deletion in the encoded protein and is common in areas where Plasmodium falciparum malaria is endemic. One null mutation in this gene is known, resulting in very severe anemia and nephrocalcinosis. [provided by RefSeq, Jul 2008]

SLC4A1 Gene-Disease associations (from GenCC):

• autosomal dominant distal renal tubular acidosis

  Inheritance: AD, AR Classification: STRONG, SUPPORTIVE Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), G2P
• cryohydrocytosis

  Inheritance: AD, Unknown Classification: STRONG, SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), PanelApp Australia
• hereditary spherocytosis type 4

  Inheritance: AD Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)
• southeast Asian ovalocytosis

  Inheritance: AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• renal tubular acidosis, distal, 4, with hemolytic anemia

  Inheritance: AR, AD Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), PanelApp Australia, Orphanet
• dehydrated hereditary stomatocytosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• hereditary spherocytosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 9 ACMG points.

• PM1: In a hotspot region, there are 2 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 9 uncertain in NM_000342.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr17-44251588-C-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 992923.
• PP3: Splicing predictors support a deleterious effect. Scorers claiming Pathogenic: dbscSNV1_ADA, dbscSNV1_RF. No scorers claiming Uncertain. Scorers claiming Benign: max_spliceai.
• PP5: Variant 17-44251588-C-T is Pathogenic according to our data. Variant chr17-44251588-C-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 17760.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000342.4. 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
	SLC4A1	NM_000342.4	MANE Select	c.2312G>A	p.Gly771Asp	missense splice_region	Exon 18 of 20	NP_000333.1	P02730-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	SLC4A1	ENST00000262418.12	TSL:1 MANE Select	c.2312G>A	p.Gly771Asp	missense splice_region	Exon 18 of 20	ENSP00000262418.6	P02730-1
	SLC4A1	ENST00000399246.3	TSL:5	c.1214G>A	p.Gly405Asp	missense splice_region	Exon 13 of 15	ENSP00000382190.3	A0A0A0MS98

Frequencies

GnomAD3 genomes AF: 0.00000657 AC: 1 AN: 152126 Hom.: 0 Cov.: 32

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 Cov.: 33

GnomAD4 genome AF: 0.00000657 AC: 1 AN: 152126 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74326

African (AFR) AF: 0.0000241 AC: 1 AN: 41422

American (AMR) AF: 0.00 AC: 0 AN: 15274

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.00 AC: 0 AN: 4828

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10610

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68014

Other (OTH) AF: 0.00 AC: 0 AN: 2084

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Hereditary spherocytosis type 4 (1)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.45	D
BayesDel_noAF	Pathogenic	0.42
CADD	Pathogenic	33
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D
Eigen	Pathogenic	1.0
Eigen_PC	Pathogenic	0.90
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D
M_CAP	Uncertain	0.096	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Pathogenic	3.9	H
PhyloP100		6.1
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-6.0	D
REVEL	Pathogenic	0.95
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.0030	D
Polyphen		1.0	D
Vest4		0.98
MutPred		0.97		Loss of helix (P = 0.0237)
MVP		0.96
MPC		1.3
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.98
gMVP		0.99
Mutation Taster		=3/97	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.87
SpliceAI score (max)		0.010		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: rs121912741; hg19: chr17-42328956;