14-22774089-A-G

Variant summary

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

The NM_003982.4(SLC7A7):c.1273T>C(p.Cys425Arg) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,884 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 Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. C425C) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: SLC7A7 NM_003982.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter P:1 U:1
• Conservation: PhyloP100: 9.32

Genes affected

SLC7A7 (HGNC:11065): (solute carrier family 7 member 7) The protein encoded by this gene is the light subunit of a cationic amino acid transporter. This sodium-independent transporter is formed when the light subunit encoded by this gene dimerizes with the heavy subunit transporter protein SLC3A2. This transporter is found in epithelial cell membranes where it transfers cationic and large neutral amino acids from the cell to the extracellular space. Defects in this gene are a cause of lysinuric protein intolerance (LPI). Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2011]

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, 0.988

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SLC7A7	NM_003982.4	c.1273T>C	p.Cys425Arg	missense_variant	9/10	ENST00000674313.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SLC7A7	ENST00000674313.1	c.1273T>C	p.Cys425Arg	missense_variant	9/10		NM_003982.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1461884 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727242

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000270

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Pathogenic:1 Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Lysinuric protein intolerance Pathogenic:1 Uncertain:1

Uncertain significance, criteria provided, single submitter	clinical testing	Invitae	Mar 22, 2022	This sequence change replaces cysteine, which is neutral and slightly polar, with arginine, which is basic and polar, at codon 425 of the SLC7A7 protein (p.Cys425Arg). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with lysinuric protein intolerance (PMID: 18716612). In at least one individual the data is consistent with being in trans (on the opposite chromosome) from a pathogenic variant. ClinVar contains an entry for this variant (Variation ID: 56354). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Tolerated"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C0"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -
Likely pathogenic, no assertion criteria provided	literature only	Juha Muilu Group; Institute for Molecular Medicine Finland (FIMM)	-	- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.99
BayesDel_addAF	Pathogenic	0.47	D
BayesDel_noAF	Pathogenic	0.44
Cadd	Pathogenic	30
Dann	Uncertain	1.0
DEOGEN2	Pathogenic	0.92	D;D;D;D;D;D
Eigen	Pathogenic	0.96
Eigen_PC	Pathogenic	0.93
FATHMM_MKL	Pathogenic	0.98	D
M_CAP	Benign	0.080	D
MetaRNN	Pathogenic	0.99	D;D;D;D;D;D
MetaSVM	Pathogenic	0.91	D
MutationAssessor	Pathogenic	3.7	H;H;H;H;H;.
MutationTaster	Benign	1.0	D;D;D;D;D;D
PrimateAI	Uncertain	0.70	T
PROVEAN	Pathogenic	-5.1	D;D;D;D;D;D
REVEL	Pathogenic	0.86
Sift	Uncertain	0.0040	D;D;D;D;D;D
Sift4G	Benign	0.068	T;T;T;T;T;D
Polyphen		0.97	D;D;D;D;D;.
Vest4		0.97
MutPred		0.97		Gain of methylation at C425 (P = 0.0155);Gain of methylation at C425 (P = 0.0155);Gain of methylation at C425 (P = 0.0155);Gain of methylation at C425 (P = 0.0155);Gain of methylation at C425 (P = 0.0155);.;
MVP		0.81
MPC		0.97
ClinPred		1.0	D
GERP RS		6.1
Varity_R		0.97
gMVP		0.94

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs386833802; hg19: chr14-23243298;