X-74421696-A-G

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_006517.5(SLC16A2):c.59A>G(p.Gln20Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000186 in 1,076,502 control chromosomes in the GnomAD database, with no homozygous occurrence. There are no hemizygote samples in GnomAD. In-silico tool predicts a benign outcome for this variant. 12/18 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 23)
  • Exomes 𝑓: 0.0000019 (0 hom. 0 hem.)
• Consequence: SLC16A2 NM_006517.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.211

Genes affected

SLC16A2 (HGNC:10923): (solute carrier family 16 member 2) This gene encodes an integral membrane protein that functions as a transporter of thyroid hormone. The encoded protein facilitates the cellular importation of thyroxine (T4), triiodothyronine (T3), reverse triiodothyronine (rT3) and diidothyronine (T2). This gene is expressed in many tissues and likely plays an important role in the development of the central nervous system. Loss of function mutations in this gene are associated with psychomotor retardation in males while females exhibit no neurological defects and more moderate thyroid-deficient phenotypes. This gene is subject to X-chromosome inactivation. Mutations in this gene are the cause of Allan-Herndon-Dudley syndrome. [provided by RefSeq, Mar 2012]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.041683167).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
SLC16A2	NM_006517.5	c.59A>G	p.Gln20Arg	missense_variant	1/6	ENST00000587091.6

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
SLC16A2	ENST00000587091.6	c.59A>G	p.Gln20Arg	missense_variant	1/6	1	NM_006517.5	P1

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD3 exomes AF: 0.00000705 AC: 1 AN: 141910 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 43600

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000165

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000186 AC: 2 AN: 1076502 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 349112

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: 0.00000240

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 23

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Spastic paraplegia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Invitae

Oct 09, 2023

This sequence change replaces glutamine, which is neutral and polar, with arginine, which is basic and polar, at codon 20 of the SLC16A2 protein (p.Gln20Arg). The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the gnomAD database. This variant has not been reported in the literature in individuals affected with SLC16A2-related conditions. Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is not expected to disrupt SLC16A2 protein function. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.062
BayesDel_addAF	Benign	-0.33	T
BayesDel_noAF	Benign	-0.71
Cadd	Benign	6.3
Dann	Benign	0.92
DEOGEN2	Benign	0.11	T
FATHMM_MKL	Benign	0.71	D
LIST_S2	Benign	0.31	T
M_CAP	Uncertain	0.14	D
MetaRNN	Benign	0.042	T
MetaSVM	Benign	-0.93	T
MutationAssessor	Benign	0.34	N
MutationTaster	Benign	1.0	N;N
PrimateAI	Benign	0.40	T
Sift4G	Benign	0.38	T
Polyphen		0.0	B
Vest4		0.096
MutPred		0.15		Gain of helix (P = 0.2059);
MVP		0.14
MPC		1.0
ClinPred		0.047	T
GERP RS		0.67
Varity_R		0.048
gMVP		0.085

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: rs1188921948; hg19: chrX-73641531;