X-135985516-G-C

Position:

• chrX-135985516-G-C

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The ENST00000370695.8(SLC9A6):​c.14G>C​(p.Gly5Ala) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 12/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G5C) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 22)
• Consequence: SLC9A6 ENST00000370695.8 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.34

Genes affected

SLC9A6 (HGNC:11079): (solute carrier family 9 member A6) This gene encodes a sodium-hydrogen exchanger that is amember of the solute carrier family 9. The encoded protein localizes to early and recycling endosomes and may be involved in regulating endosomal pH and volume. Defects in this gene are associated with X-linked syndromic cognitive disability, Christianson type. Alternate splicing results in multiple transcript variants.[provided by RefSeq, Apr 2010]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.1415165).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
SLC9A6	NM_001379110.1	c.-57+39G>C		intron_variant		ENST00000630721.3	NP_001366039.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
SLC9A6	ENST00000630721.3	c.-57+39G>C		intron_variant		4	NM_001379110.1	ENSP00000487486

Frequencies

GnomAD3 genomes Cov.: 22

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 22

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Christianson syndrome Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 10, 2023

This sequence change replaces glycine, which is neutral and non-polar, with alanine, which is neutral and non-polar, at codon 5 of the SLC9A6 protein (p.Gly5Ala). 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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Not Available"; PolyPhen-2: "Not Available"; Align-GVGD: "Not Available". The alanine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. This variant has not been reported in the literature in individuals affected with SLC9A6-related conditions. This variant is not present in population databases (gnomAD no frequency). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.090
BayesDel_addAF	Benign	-0.35	T
BayesDel_noAF	Benign	-0.74
CADD	Benign	18
DANN	Uncertain	0.98
DEOGEN2	Benign	0.12	.;T
FATHMM_MKL	Benign	0.55	D
LIST_S2	Benign	0.73	T;T
M_CAP	Pathogenic	0.65	D
MetaRNN	Benign	0.14	T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.14	N;N
MutationTaster	Benign	1.0	D;N;N
PrimateAI	Pathogenic	0.85	D
PROVEAN	Benign	-0.39	N;N
REVEL	Benign	0.13
Sift	Benign	0.16	T;T
Sift4G	Pathogenic	0.0	D;D
Polyphen		0.0	B;B
Vest4		0.18
MutPred		0.36		Gain of helix (P = 0.0034);Gain of helix (P = 0.0034);
MVP		0.13
MPC		1.1
ClinPred		0.092	T
GERP RS		4.0
Varity_R		0.13
gMVP		0.63

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: rs2089318307; hg19: chrX-135067675;