16-74774639-G-C

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PS1PM1PM2PP3_StrongPP5_Moderate

The NM_024306.5(FA2H):​c.117C>G​(p.Phe39Leu) variant causes a missense change. The variant allele was found at a frequency of 0.00000268 in 1,490,922 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 Pathogenic (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar.

Frequency

Genomes: 𝑓 0.0000066 ( 0 hom., cov: 33)
Exomes 𝑓: 0.0000022 ( 0 hom. )

Consequence

FA2H
NM_024306.5 missense

Scores

12
4
3

Clinical Significance

Pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 4.67

Publications

1 publications found
Variant links:
Genes affected
FA2H (HGNC:21197): (fatty acid 2-hydroxylase) This gene encodes a protein that catalyzes the synthesis of 2-hydroxysphingolipids, a subset of sphingolipids that contain 2-hydroxy fatty acids. Sphingolipids play roles in many cellular processes and their structural diversity arises from modification of the hydrophobic ceramide moiety, such as by 2-hydroxylation of the N-acyl chain, and the existence of many different head groups. Mutations in this gene have been associated with leukodystrophy dysmyelinating with spastic paraparesis with or without dystonia.[provided by RefSeq, Mar 2010]
FA2H Gene-Disease associations (from GenCC):
  • hereditary spastic paraplegia 35
    Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae), G2P

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Pathogenic. The variant received 14 ACMG points.

PS1
Transcript NM_024306.5 (FA2H) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
PM1
In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 8 uncertain in NM_024306.5
PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.948
PP5
Variant 16-74774639-G-C is Pathogenic according to our data. Variant chr16-74774639-G-C is described in ClinVar as Pathogenic. ClinVar VariationId is 2194147.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
FA2HNM_024306.5 linkc.117C>G p.Phe39Leu missense_variant Exon 1 of 7 ENST00000219368.8 NP_077282.3 Q7L5A8-1
FA2HXM_011523317.4 linkc.117C>G p.Phe39Leu missense_variant Exon 1 of 6 XP_011521619.1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
FA2HENST00000219368.8 linkc.117C>G p.Phe39Leu missense_variant Exon 1 of 7 1 NM_024306.5 ENSP00000219368.3 Q7L5A8-1
FA2HENST00000567683.5 linkn.117C>G non_coding_transcript_exon_variant Exon 1 of 5 2 ENSP00000455126.1 H3BP32

Frequencies

GnomAD3 genomes
AF:
0.00000657
AC:
1
AN:
152096
Hom.:
0
Cov.:
33
show subpopulations
Gnomad AFR
AF:
0.0000241
Gnomad AMI
AF:
0.00
Gnomad AMR
AF:
0.00
Gnomad ASJ
AF:
0.00
Gnomad EAS
AF:
0.00
Gnomad SAS
AF:
0.00
Gnomad FIN
AF:
0.00
Gnomad MID
AF:
0.00
Gnomad NFE
AF:
0.00
Gnomad OTH
AF:
0.00
GnomAD4 exome
AF:
0.00000224
AC:
3
AN:
1338826
Hom.:
0
Cov.:
33
AF XY:
0.00000303
AC XY:
2
AN XY:
660618
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
27594
American (AMR)
AF:
0.00
AC:
0
AN:
30194
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
23676
East Asian (EAS)
AF:
0.00
AC:
0
AN:
30040
South Asian (SAS)
AF:
0.00
AC:
0
AN:
73836
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
34082
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
4186
European-Non Finnish (NFE)
AF:
0.00000283
AC:
3
AN:
1059432
Other (OTH)
AF:
0.00
AC:
0
AN:
55786
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.475
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
GnomAD4 genome
AF:
0.00000657
AC:
1
AN:
152096
Hom.:
0
Cov.:
33
AF XY:
0.00
AC XY:
0
AN XY:
74308
show subpopulations
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.
African (AFR)
AF:
0.0000241
AC:
1
AN:
41440
American (AMR)
AF:
0.00
AC:
0
AN:
15278
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
3472
East Asian (EAS)
AF:
0.00
AC:
0
AN:
5174
South Asian (SAS)
AF:
0.00
AC:
0
AN:
4834
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
10598
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
314
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
67982
Other (OTH)
AF:
0.00
AC:
0
AN:
2092
⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.375
Heterozygous variant carriers
0
0
1
1
2
2
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance
Alfa
AF:
0.00
Hom.:
0

ClinVar

Significance: Pathogenic
Submissions summary: Pathogenic:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

Spastic paraplegia Pathogenic:1
Jul 23, 2022
Labcorp Genetics (formerly Invitae), Labcorp
Significance:Pathogenic
Review Status:criteria provided, single submitter
Collection Method:clinical testing

For these reasons, this variant has been classified as Pathogenic. 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 FA2H protein function. A different variant (c.117C>A) giving rise to the same protein effect has been determined to be pathogenic (PMID: 25732363; Invitae). This suggests that this variant is also likely to be causative of disease. This variant is present in population databases (no rsID available, gnomAD 0.01%). This sequence change replaces phenylalanine, which is neutral and non-polar, with leucine, which is neutral and non-polar, at codon 39 of the FA2H protein (p.Phe39Leu). -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.97
BayesDel_addAF
Pathogenic
0.41
D
BayesDel_noAF
Pathogenic
0.35
CADD
Pathogenic
28
DANN
Uncertain
1.0
DEOGEN2
Pathogenic
0.86
D
Eigen
Uncertain
0.65
Eigen_PC
Uncertain
0.57
FATHMM_MKL
Benign
0.74
D
LIST_S2
Benign
0.65
T
M_CAP
Pathogenic
0.99
D
MetaRNN
Pathogenic
0.95
D
MetaSVM
Uncertain
0.46
D
MutationAssessor
Pathogenic
3.0
M
PhyloP100
4.7
PrimateAI
Pathogenic
0.97
D
PROVEAN
Pathogenic
-5.0
D
REVEL
Pathogenic
0.96
Sift
Pathogenic
0.0
D
Sift4G
Pathogenic
0.0
D
Polyphen
1.0
D
Vest4
0.51
MutPred
0.83
Loss of stability (P = 0.0631);
MVP
0.72
MPC
2.8
ClinPred
1.0
D
GERP RS
4.1
PromoterAI
0.053
Neutral
Varity_R
0.87
gMVP
0.89

Splicing

Name
Calibrated prediction
Score
Prediction
SpliceAI score (max)
0.010
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: rs794729215; hg19: chr16-74808537; API