rs118203975

Positions:

• chr4-127930752-C-G
• chr4-127930752-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 8 ACMG points: 8P and 0B. PM2 PM5 PP3_Strong

The NM_001371596.2(MFSD8):​c.929G>C​(p.Gly310Ala) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,312 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G310D) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: MFSD8 NM_001371596.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.61

Genes affected

MFSD8 (HGNC:28486): (major facilitator superfamily domain containing 8) This gene encodes a ubiquitous integral membrane protein that contains a transporter domain and a major facilitator superfamily (MFS) domain. Other members of the major facilitator superfamily transport small solutes through chemiosmotic ion gradients. The substrate transported by this protein is unknown. The protein likely localizes to lysosomal membranes. Mutations in this gene are correlated with a variant form of late infantile-onset neuronal ceroid lipofuscinoses (vLINCL). [provided by RefSeq, Oct 2008]

ACMG classification

Verdict is Likely_pathogenic. Variant got 8 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr4-127930752-C-T is described in Lovd as [Likely_pathogenic].
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.95

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
MFSD8	NM_001371596.2	c.929G>C	p.Gly310Ala	missense_variant	9/12	ENST00000641686.2	NP_001358525.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
MFSD8	ENST00000641686.2	c.929G>C	p.Gly310Ala	missense_variant	9/12		NM_001371596.2	ENSP00000493218	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461312 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 726934

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: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuronal ceroid lipofuscinosis 7 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 31, 2021

This sequence change replaces glycine with alanine at codon 310 of the MFSD8 protein (p.Gly310Ala). The glycine residue is highly conserved and there is a small physicochemical difference between glycine and alanine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with MFSD8-related conditions. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.28
BayesDel_addAF	Pathogenic	0.30	D
BayesDel_noAF	Pathogenic	0.20
CADD	Pathogenic	26
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.48	T;T;.;.;.;.;.;.;.;.;.;.;.;.
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.40
FATHMM_MKL	Pathogenic	1.0	D
LIST_S2	Pathogenic	0.98	.;.;D;D;D;.;D;D;D;D;D;D;D;D
M_CAP	Benign	0.032	D
MetaRNN	Pathogenic	0.95	D;D;D;D;D;D;D;D;D;D;D;D;D;D
MetaSVM	Benign	-0.33	T
MutationAssessor	Uncertain	2.6	M;M;.;.;.;.;.;.;.;.;.;.;.;.
MutationTaster	Benign	1.0	D;D;D
PrimateAI	Uncertain	0.61	T
PROVEAN	Pathogenic	-5.2	.;D;.;.;.;.;.;.;.;.;.;.;.;.
REVEL	Uncertain	0.50
Sift	Benign	0.082	.;T;.;.;.;.;.;.;.;.;.;.;.;.
Sift4G	Pathogenic	0.0	.;D;.;.;.;.;.;.;.;.;.;.;.;.
Polyphen		1.0	D;D;.;.;.;.;.;.;.;.;.;.;.;.
Vest4		0.98
MutPred		0.83		Loss of stability (P = 0.0485);Loss of stability (P = 0.0485);.;.;.;.;.;.;Loss of stability (P = 0.0485);.;.;.;Loss of stability (P = 0.0485);.;
MVP		0.77
MPC		0.50
ClinPred		0.99	D
GERP RS		5.0
Varity_R		0.46
gMVP		0.95

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr4-128851907;