chr16-74719012-G-A

Variant names:

• chr16-74719012-G-A
• rs797045569
• NM_024306.5:c.762C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Moderate BP6 BP7

The NM_024306.5(FA2H):​c.762C>T​(p.Phe254Phe) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000161 in 1,613,942 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000016 (0 hom.)
• Consequence: FA2H NM_024306.5 synonymous
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications U:1 B:1
• Conservation: PhyloP100: 2.94
• Publications: 0 publications found

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), ClinGen, G2P

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.38).
• BP6: Variant 16-74719012-G-A is Benign according to our data. Variant chr16-74719012-G-A is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 210969.
• BP7: Synonymous conserved (PhyloP=2.94 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_024306.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FA2H	NM_024306.5	MANE Select	c.762C>T	p.Phe254Phe	synonymous	Exon 5 of 7	NP_077282.3

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	FA2H	ENST00000219368.8	TSL:1 MANE Select	c.762C>T	p.Phe254Phe	synonymous	Exon 5 of 7	ENSP00000219368.3	Q7L5A8-1
	FA2H	ENST00000888352.1		c.756C>T	p.Phe252Phe	synonymous	Exon 5 of 7	ENSP00000558411.1
	FA2H	ENST00000888351.1		c.762C>T	p.Phe254Phe	synonymous	Exon 5 of 7	ENSP00000558410.1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152248 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.0000241

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000654

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: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.0000157 AC: 23 AN: 1461576 Hom.: 0 Cov.: 33 AF XY: 0.0000124 AC XY: 9 AN XY: 727048

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

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

Ashkenazi Jewish (ASJ) AF: 0.0000383 AC: 1 AN: 26136

East Asian (EAS) AF: 0.0000504 AC: 2 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86254

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53114

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.0000135 AC: 15 AN: 1112006

Other (OTH) AF: 0.0000828 AC: 5 AN: 60396

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152366 Hom.: 0 Cov.: 32 AF XY: 0.0000134 AC XY: 1 AN XY: 74504

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.0000240 AC: 1 AN: 41588

American (AMR) AF: 0.0000653 AC: 1 AN: 15310

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5182

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10626

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68040

Other (OTH) AF: 0.00 AC: 0 AN: 2112

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.00109982), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.0000227

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.38
CADD	Benign	12
DANN	Benign	0.74
PhyloP100		2.9

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

Other links and lift over

dbSNP: rs797045569; hg19: chr16-74752910; COSMIC: COSV54726969; COSMIC: COSV54726969;