2-227699528-A-T

Position:

• chr2-227699528-A-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PM2 PP3_Strong

The NM_025243.4(SLC19A3):​c.187T>A​(p.Tyr63Asn) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: SLC19A3 NM_025243.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 9.31

Genes affected

SLC19A3 (HGNC:16266): (solute carrier family 19 member 3) This gene encodes a ubiquitously expressed transmembrane thiamine transporter that lacks folate transport activity. Mutations in this gene cause biotin-responsive basal ganglia disease (BBGD); a recessive disorder manifested in childhood that progresses to chronic encephalopathy, dystonia, quadriparesis, and death if untreated. Patients with BBGD have bilateral necrosis in the head of the caudate nucleus and in the putamen. Administration of high doses of biotin in the early progression of the disorder eliminates pathological symptoms while delayed treatment results in residual paraparesis, mild cognitive disability, or dystonia. Administration of thiamine is ineffective in the treatment of this disorder. Experiments have failed to show that this protein can transport biotin. Mutations in this gene also cause a Wernicke's-like encephalopathy.[provided by RefSeq, Jan 2010]

ACMG classification

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.957

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SLC19A3	NM_025243.4	c.187T>A	p.Tyr63Asn	missense_variant	3/6	ENST00000644224.2	NP_079519.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SLC19A3	ENST00000644224.2	c.187T>A	p.Tyr63Asn	missense_variant	3/6		NM_025243.4	ENSP00000495385	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 33

GnomAD4 genome Cov.: 32

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.20
BayesDel_addAF	Pathogenic	0.33	D
BayesDel_noAF	Pathogenic	0.23
CADD	Pathogenic	27
DANN	Uncertain	0.98
DEOGEN2	Uncertain	0.74	D;.;D;.;.;.
Eigen	Uncertain	0.44
Eigen_PC	Uncertain	0.43
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Uncertain	0.92	.;D;D;D;D;D
M_CAP	Uncertain	0.15	D
MetaRNN	Pathogenic	0.96	D;D;D;D;D;D
MetaSVM	Uncertain	0.55	D
MutationAssessor	Pathogenic	3.0	M;.;M;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.69	T
PROVEAN	Pathogenic	-8.2	.;D;D;.;.;D
REVEL	Pathogenic	0.72
Sift	Benign	0.074	.;T;T;.;.;T
Sift4G	Uncertain	0.041	.;D;D;.;.;.
Polyphen		0.99	D;.;D;.;.;.
Vest4		0.92, 0.93
MutPred		0.80		Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);Gain of sheet (P = 0.0827);.;.;Gain of sheet (P = 0.0827);
MVP		0.97
MPC		0.46
ClinPred		0.99	D
GERP RS		5.9
Varity_R		0.48
gMVP		0.78

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: rs144817990; hg19: chr2-228564244;