NM_001003841.3:c.1173+2T>C

Variant names:

• chr5-1216947-T-C
• rs142979576
• NM_001003841.3:c.1173+2T>C

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_001003841.3(SLC6A19):​c.1173+2T>C variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000434 in 1,612,408 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 35)
  • Exomes 𝑓: 0.0000034 (0 hom.)
• Consequence: SLC6A19 NM_001003841.3 splice_donor, intron
• Scores: Splicing: ADA: 0.9651
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 5.46
• Publications: 6 publications found

Genes affected

SLC6A19 (HGNC:27960): (solute carrier family 6 member 19) This gene encodes a system B(0) transmembrane protein that actively transports most neutral amino acids across the apical membrane of epithelial cells. Mutations in this gene may result in Hartnup disorder, an inherited disease with symptoms such as pellagra, cerebellar ataxia, and psychosis. The expression and function of B0AT1 (SLC6A19) in intestinal cells depends on the presence of the accessory protein angiotensin-converting enzyme 2 (ACE2) which, among other functions, acts as a chaperone for membrane trafficking of B0AT1. The ACE2 is also the cellular receptor for severe acute respiratory syndrome-coronavirus (SARS-CoV) and for SARS-CoV-2 that is causing the coronavirus 2019 (COVID-19) pandemic [provided by RefSeq, Jul 2020]

SLC6A19 Gene-Disease associations (from GenCC):

• Hartnup disease

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae), ClinGen

ACMG classification

Our verdict: Pathogenic. The variant received 18 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
• PP5: Variant 5-1216947-T-C is Pathogenic according to our data. Variant chr5-1216947-T-C is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 3339144.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
SLC6A19	NM_001003841.3	c.1173+2T>C		splice_donor_variant, intron_variant	Intron 8 of 11	ENST00000304460.11	NP_001003841.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
SLC6A19	ENST00000304460.11	c.1173+2T>C		splice_donor_variant, intron_variant	Intron 8 of 11	1	NM_001003841.3	ENSP00000305302.10
SLC6A19	ENST00000515652.5	n.*118+2T>C		splice_donor_variant, intron_variant	Intron 7 of 10	2		ENSP00000425701.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152220 Hom.: 0 Cov.: 35

Gnomad AFR AF: 0.0000482

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

GnomAD2 exomes AF: 0.00000801 AC: 2 AN: 249668 AF XY: 0.00000739

Gnomad AFR exome AF: 0.0000616

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000892

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000342 AC: 5 AN: 1460188 Hom.: 0 Cov.: 36 AF XY: 0.00000413 AC XY: 3 AN XY: 726400

African (AFR) AF: 0.0000299 AC: 1 AN: 33454

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26134

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86208

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52654

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5064

European-Non Finnish (NFE) AF: 0.00000360 AC: 4 AN: 1111958

Other (OTH) AF: 0.00 AC: 0 AN: 60292

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152220 Hom.: 0 Cov.: 35 AF XY: 0.0000134 AC XY: 1 AN XY: 74366

African (AFR) AF: 0.0000482 AC: 2 AN: 41454

American (AMR) AF: 0.00 AC: 0 AN: 15286

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: 4838

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10628

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

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 68026

Other (OTH) AF: 0.00 AC: 0 AN: 2094

Alfa AF: 0.000235 Hom.: 0

Bravo AF: 0.0000151

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Neutral 1 amino acid transport defect Pathogenic:1

Jul 03, 2024

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Variant summary: SLC6A19 c.1173+2T>C is located in a canonical splice-site and is predicted to affect mRNA splicing resulting in a significantly altered protein due to either exon skipping, shortening, or inclusion of intronic material. Several computational tools predict a significant impact on normal splicing: Three predict the variant abolishes the canonical 5' splicing donor site. Two predict the variant creates a cryptic 5' donor site. One predict the variant no significant impact on splicing. However, these predictions have yet to be confirmed by functional studies. The variant allele was found at a frequency of 8e-06 in 249668 control chromosomes. To our knowledge, no occurrence of c.1173+2T>C in individuals affected with Hartnup Disease and no experimental evidence demonstrating its impact on protein function have been reported. No submitters have cited clinical-significance assessments for this variant to ClinVar. Based on the evidence outlined above, the variant was classified as likely pathogenic. -

not provided Pathogenic:1

Mar 02, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 8 of the SLC6A19 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in SLC6A19 are known to be pathogenic (PMID: 15286787, 15286788). This variant is present in population databases (rs142979576, gnomAD 0.008%). Disruption of this splice site has been observed in individuals with Hartnup disorder (PMID: 15286787, 15286788). Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Benign	-0.21
CADD	Uncertain	25
DANN	Benign	0.92
Eigen	Uncertain	0.61
Eigen_PC	Uncertain	0.33
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		5.5
GERP RS		3.7
Mutation Taster		=5/95	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	0.97
dbscSNV1_RF	Benign	0.59
SpliceAI score (max)		0.50		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.50		Position offset: 2
DS_DL_spliceai		0.24		Position offset: -2

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

Other links and lift over

dbSNP: rs142979576; hg19: chr5-1217062;