chr4-127921552-T-C

Variant summary

Our verdict is Uncertain significance. The variant received 2 ACMG points: 2P and 0B. PP3_Moderate

The NM_001371596.2(MFSD8):​c.1322A>G​(p.Tyr441Cys) variant causes a missense change. The variant allele was found at a frequency of 0.00000684 in 1,461,854 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. Y441F) has been classified as Uncertain significance.

Frequency

Genomes: not found (cov: 32)
Exomes 𝑓: 0.0000068 ( 0 hom. )

Consequence

MFSD8
NM_001371596.2 missense

Scores

9
5
4

Clinical Significance

Uncertain significance criteria provided, multiple submitters, no conflicts U:3

Conservation

PhyloP100: 6.99

Publications

1 publications found
Variant links:
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]
MFSD8 Gene-Disease associations (from GenCC):
  • neuronal ceroid lipofuscinosis
    Inheritance: AR Classification: DEFINITIVE Submitted by: ClinGen
  • neuronal ceroid lipofuscinosis 7
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet, G2P
  • macular dystrophy with central cone involvement
    Inheritance: AR Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Uncertain_significance. The variant received 2 ACMG points.

PP3
MetaRNN computational evidence supports a deleterious effect, 0.893

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
MFSD8NM_001371596.2 linkc.1322A>G p.Tyr441Cys missense_variant Exon 11 of 12 ENST00000641686.2 NP_001358525.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
MFSD8ENST00000641686.2 linkc.1322A>G p.Tyr441Cys missense_variant Exon 11 of 12 NM_001371596.2 ENSP00000493218.2

Frequencies

GnomAD3 genomes
Cov.:
32
GnomAD2 exomes
AF:
0.0000358
AC:
9
AN:
251270
AF XY:
0.0000368
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.000231
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.000163
GnomAD4 exome
AF:
0.00000684
AC:
10
AN:
1461854
Hom.:
0
Cov.:
32
AF XY:
0.00000825
AC XY:
6
AN XY:
727226
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33480
American (AMR)
AF:
0.000224
AC:
10
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26132
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86258
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53406
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5768
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1111992
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.520
Heterozygous variant carriers
0
1
2
3
4
5
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
32
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.0000151
ExAC
AF:
0.0000247
AC:
3

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:3
Revision: criteria provided, multiple submitters, no conflicts
LINK: link

Submissions by phenotype

Inborn genetic diseases Uncertain:1
Jan 31, 2019
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The p.Y441C variant (also known as c.1322A>G), located in coding exon 11 of the MFSD8 gene, results from an A to G substitution at nucleotide position 1322. The tyrosine at codon 441 is replaced by cysteine, an amino acid with highly dissimilar properties. This amino acid position is highly conserved in available vertebrate species. In addition, this alteration is predicted to be deleterious by in silico analysis. Since supporting evidence is limited at this time, the clinical significance of this alteration remains unclear.

Late-infantile neuronal ceroid lipofuscinosis Uncertain:1
Nov 11, 2019
Natera, Inc.
Significance:Uncertain significance
Review Status:no assertion criteria provided
Collection Method:clinical testing

Neuronal ceroid lipofuscinosis 7 Uncertain:1
Jan 24, 2024
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

This sequence change replaces tyrosine, which is neutral and polar, with cysteine, which is neutral and slightly polar, at codon 441 of the MFSD8 protein (p.Tyr441Cys). This variant is present in population databases (rs749153763, gnomAD 0.02%). This variant has not been reported in the literature in individuals affected with MFSD8-related conditions. ClinVar contains an entry for this variant (Variation ID: 533375). 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 expected to disrupt MFSD8 protein function with a positive predictive value of 80%. 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
Uncertain
0.50
BayesDel_addAF
Pathogenic
0.17
D
BayesDel_noAF
Pathogenic
0.30
CADD
Pathogenic
26
DANN
Uncertain
1.0
DEOGEN2
Benign
0.34
T;T;.;.;.;.;.;.;.;.
Eigen
Pathogenic
0.73
Eigen_PC
Pathogenic
0.68
FATHMM_MKL
Pathogenic
0.98
D
LIST_S2
Benign
0.0
.;.;D;D;D;.;D;D;D;D
M_CAP
Uncertain
0.13
D
MetaRNN
Pathogenic
0.89
D;D;D;D;D;D;D;D;D;D
MetaSVM
Uncertain
0.26
D
MutationAssessor
Pathogenic
3.3
M;M;.;.;.;.;.;.;.;.
PhyloP100
7.0
PrimateAI
Uncertain
0.74
T
PROVEAN
Benign
0.0
.;D;.;.;.;.;.;.;.;.
REVEL
Benign
0.0
Sift
Pathogenic
0.0
.;D;.;.;.;.;.;.;.;.
Sift4G
Pathogenic
0.0
.;D;.;.;.;.;.;.;.;.
Vest4
0.0
ClinPred
0.94
D
GERP RS
5.2
Varity_R
0.61
gMVP
0.96
Mutation Taster
=28/72
disease causing

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

Other links and lift over

dbSNP: rs749153763; hg19: chr4-128842707; COSMIC: COSV56552809; COSMIC: COSV56552809; API