chr16-74713670-C-T

Position:

• chr16-74713670-C-T

Variant summary

Our verdict is Benign. Variant got -14 ACMG points: 0P and 14B. BP4_Strong BP6_Moderate BS1 BS2

The NM_024306.5(FA2H):​c.*520G>A variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00494 in 156,930 control chromosomes in the GnomAD database, including 3 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★).

• Frequency:
  • Genomes: 𝑓 0.0049 (3 hom., cov: 33)
  • Exomes 𝑓: 0.0057 (0 hom.)
• Consequence: FA2H NM_024306.5 3_prime_UTR
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.965

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]

ACMG classification

Verdict is Benign. Variant got -14 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.92).
• BP6: Variant 16-74713670-C-T is Benign according to our data. Variant chr16-74713670-C-T is described in ClinVar as [Likely_benign]. Clinvar id is 320478.Status of the report is criteria_provided_single_submitter, 1 stars.
• BS1: Variant frequency is greater than expected in population nfe. gnomad4 allele frequency = 0.00492 (749/152346) while in subpopulation NFE AF= 0.00753 (512/68028). AF 95% confidence interval is 0.00699. There are 3 homozygotes in gnomad4. There are 355 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck.
• BS2: High Homozygotes in GnomAd4 at 3 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
FA2H	NM_024306.5	c.*520G>A		3_prime_UTR_variant	7/7	ENST00000219368.8	NP_077282.3
FA2H	XM_011523319.3	c.*520G>A		3_prime_UTR_variant	7/7		XP_011521621.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
FA2H	ENST00000219368.8	c.*520G>A		3_prime_UTR_variant	7/7	1	NM_024306.5	ENSP00000219368	P1
FA2H	ENST00000562145.1	n.1360G>A		non_coding_transcript_exon_variant	2/2	1
FA2H	ENST00000567683.5	c.*918G>A		3_prime_UTR_variant, NMD_transcript_variant	5/5	2		ENSP00000455126

Frequencies

GnomAD3 genomes AF: 0.00492 AC: 749 AN: 152228 Hom.: 3 Cov.: 33

Gnomad AFR AF: 0.00111

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00700

Gnomad ASJ AF: 0.00634

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00186

Gnomad FIN AF: 0.00320

Gnomad MID AF: 0.00318

Gnomad NFE AF: 0.00753

Gnomad OTH AF: 0.00860

GnomAD4 exome AF: 0.00567 AC: 26 AN: 4584 Hom.: 0 Cov.: 0 AF XY: 0.00581 AC XY: 14 AN XY: 2408

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00509

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00298

Gnomad4 FIN exome AF: 0.00943

Gnomad4 NFE exome AF: 0.00723

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.00492 AC: 749 AN: 152346 Hom.: 3 Cov.: 33 AF XY: 0.00477 AC XY: 355 AN XY: 74496

Gnomad4 AFR AF: 0.00111

Gnomad4 AMR AF: 0.00699

Gnomad4 ASJ AF: 0.00634

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00186

Gnomad4 FIN AF: 0.00320

Gnomad4 NFE AF: 0.00753

Gnomad4 OTH AF: 0.00851

Alfa AF: 0.00603 Hom.: 0

Bravo AF: 0.00510

Asia WGS AF: 0.00144 AC: 5 AN: 3478

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary spastic paraplegia 35 Benign:1

Likely benign, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score and internal cut-off values, a variant classified as likely benign is not then subjected to further curation. The score for this variant resulted in a classification of likely benign for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.92
CADD	Benign	2.1
DANN	Benign	0.68

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

LitVar

Other links and lift over

dbSNP: rs187456324; hg19: chr16-74747568;