chr8-144354670-G-A

Position:

• chr8-144354670-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 1 ACMG points: 2P and 1B. PM2 BP4

The NM_001280561.2(TMEM249):​c.98C>T​(p.Ala33Val) 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. Variant has been reported in ClinVar as Uncertain significance (no stars).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: TMEM249 NM_001280561.2 missense
• Clinical Significance: Uncertain significance no assertion criteria provided U:1
• Conservation: PhyloP100: 3.43

Genes affected

TMEM249 (HGNC:44155): (transmembrane protein 249) Predicted to be integral component of membrane. [provided by Alliance of Genome Resources, Apr 2022]

SLC52A2 (HGNC:30224): (solute carrier family 52 member 2) This gene encodes a membrane protein which belongs to the riboflavin transporter family. In humans, riboflavin must be obtained by intestinal absorption because it cannot be synthesized by the body. The water-soluble vitamin riboflavin is processed to the coenzymes flavin mononucleotide (FMN) and flavin adenine dinucleotide (FAD) which then act as intermediaries in many cellular metabolic reactions. Paralogous members of the riboflavin transporter gene family are located on chromosomes 17 and 20. Unlike other members of this family, this gene has higher expression in brain tissue than small intestine. Alternative splicing of this gene results in multiple transcript variants encoding the same protein. Mutations in this gene have been associated with Brown-Vialetto-Van Laere syndrome 2 - an autosomal recessive progressive neurologic disorder characterized by deafness, bulbar dysfunction, and axial and limb hypotonia. [provided by RefSeq, Jul 2012]

ACMG classification

Verdict is Uncertain_significance. Variant got 1 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.32949153).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
TMEM249	NM_001280561.2	c.98C>T	p.Ala33Val	missense_variant	2/6	ENST00000696146.1
TMEM249	NM_001252402.3	c.98C>T	p.Ala33Val	missense_variant	1/5
TMEM249	NM_001252404.3	c.98C>T	p.Ala33Val	missense_variant	1/4
TMEM249	NR_047684.3	n.262C>T		non_coding_transcript_exon_variant	1/5

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
TMEM249	ENST00000696146.1	c.98C>T	p.Ala33Val	missense_variant	2/6		NM_001280561.2	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1383300 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 682598

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.000269 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: no assertion criteria provided

Submissions by phenotype

Epidermolysis bullosa simplex with nail dystrophy Uncertain:1

Uncertain significance, no assertion criteria provided

research

Department of Molecular Bıology and Genetics, Istanbul Technical University

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Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.39
BayesDel_addAF	Uncertain	0.037	T
BayesDel_noAF	Benign	-0.19
CADD	Uncertain	25
DANN	Pathogenic	1.0
DEOGEN2	Benign	0.037	T;.
Eigen	Uncertain	0.34
Eigen_PC	Uncertain	0.28
FATHMM_MKL	Uncertain	0.76	D
M_CAP	Pathogenic	0.45	D
MetaRNN	Benign	0.33	T;T
MetaSVM	Benign	-0.49	T
MutationAssessor	Benign	2.0	M;.
MutationTaster	Benign	0.94	N;N
PrimateAI	Uncertain	0.60	T
PROVEAN	Benign	-2.3	N;D
Sift	Benign	0.36	T;D
Sift4G	Pathogenic	0.0	D;.
Polyphen		1.0	D;.
Vest4		0.36
MutPred		0.21		Loss of helix (P = 0.0558);Loss of helix (P = 0.0558);
MVP		0.040
ClinPred		0.87	D
GERP RS		4.1
Varity_R		0.12
gMVP		0.22

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.060		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: rs370391854; hg19: chr8-145578330;