rs749704755

Variant names:

• chr4-127943775-C-A
• rs749704755
• NM_001371596.2:c.416G>T

Your query was ambiguous. Multiple possible variants found:

• chr4-127943775-C-A
• chr4-127943775-C-T

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM2 PM5 PP3_Strong PP5_Moderate

The NM_001371596.2(MFSD8):​c.416G>T​(p.Arg139Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000616 in 1,461,842 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 Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. R139C) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000062 (0 hom.)
• Consequence: MFSD8 NM_001371596.2 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 6.93
• Publications: 10 publications found

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)

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr4-127943776-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1001570.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.982
• PP5: Variant 4-127943775-C-A is Pathogenic according to our data. Variant chr4-127943775-C-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 1805060.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001371596.2. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MFSD8	NM_001371596.2	MANE Select	c.416G>T	p.Arg139Leu	missense	Exon 4 of 12	NP_001358525.1
	MFSD8	NM_001371591.2		c.416G>T	p.Arg139Leu	missense	Exon 4 of 12	NP_001358520.1
	MFSD8	NM_001371592.2		c.416G>T	p.Arg139Leu	missense	Exon 4 of 12	NP_001358521.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	MFSD8	ENST00000641686.2	MANE Select	c.416G>T	p.Arg139Leu	missense	Exon 4 of 12	ENSP00000493218.2
	MFSD8	ENST00000296468.8	TSL:1	c.416G>T	p.Arg139Leu	missense	Exon 5 of 13	ENSP00000296468.3
	MFSD8	ENST00000641186.1		c.416G>T	p.Arg139Leu	missense	Exon 4 of 11	ENSP00000493347.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000796 AC: 2 AN: 251244 AF XY: 0.00000737

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000616 AC: 9 AN: 1461842 Hom.: 0 Cov.: 31 AF XY: 0.00000825 AC XY: 6 AN XY: 727218

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39688

South Asian (SAS) AF: 0.00 AC: 0 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53412

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000809 AC: 9 AN: 1111994

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000756

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Neuronal ceroid lipofuscinosis 7 Pathogenic:1

Feb 02, 2022

Victorian Clinical Genetics Services, Murdoch Childrens Research Institute

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Based on the classification scheme VCGS_Germline_v1.3.4, this variant is classified as Likely pathogenic. Following criteria are met: 0102 - Loss of function is a known mechanism of disease in this gene and is associated with neuronal ceroid lipofuscinosis 7 (MIM#610951). (I) 0106 - This gene is associated with autosomal recessive disease. (I) 0200 - Variant is predicted to result in a missense amino acid change from arginine to leucine. (I) 0253 - This variant is hemizygous. (I) 0304 - Variant is present in gnomAD (v2) <0.01 for a recessive condition (2 heterozygotes, 0 homozygotes). (SP) 0309 - An alternative amino acid change at the same position has been observed in gnomAD (v2) (1 heterozygote, 0 homozygotes). (I) 0501 - Missense variant consistently predicted to be damaging by multiple in silico tools or highly conserved with a major amino acid change. (SP) 0600 - Variant is located in the annotated Major Facilitator Superfamily (DECIPHER). (I) 0703 - Other missense variants comparable to the one identified in this case have moderate previous evidence for pathogenicity. An alternative change to a histidine has been reported in two patients with ceroid lipofuscinosis (PMID: 19201763, 28708303). Another change to a cysteine has also been reported in ClinVar as both likely pathogenic and VUS. (SP) 0807 - This variant has no previous evidence of pathogenicity. (I) 0905 - No published segregation evidence has been identified for this variant. (I) 1007 - No published functional evidence has been identified for this variant. (I) 1102 - Strong phenotype match for this individual. (SP) 1206 - This variant has been shown to be paternally inherited (by trio analysis). (I) Legend: (SP) - Supporting pathogenic, (I) - Information, (SB) - Supporting benign

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.80
BayesDel_addAF	Pathogenic	0.35	D
BayesDel_noAF	Pathogenic	0.28
CADD	Pathogenic	29
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.53	D
Eigen	Pathogenic	0.73
Eigen_PC	Uncertain	0.62
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Pathogenic	0.98	D
M_CAP	Uncertain	0.28	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Uncertain	0.33	D
MutationAssessor	Pathogenic	3.2	M
PhyloP100		6.9
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-6.6	D
REVEL	Pathogenic	0.77
Sift	Uncertain	0.0020	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.97
MutPred		0.87		Loss of methylation at R139 (P = 0.0174)
MVP		0.87
MPC		0.55
ClinPred		0.99	D
GERP RS		5.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.77
gMVP		0.94
Mutation Taster		=30/70	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

Other links and lift over

dbSNP: rs749704755; hg19: chr4-128864930;