chr14-53152383-T-C

Position:

• chr14-53152383-T-C

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_001160148.2(DDHD1):​c.716A>G​(p.Gln239Arg) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,518 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 15/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: DDHD1 NM_001160148.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.0710

Genes affected

DDHD1 (HGNC:19714): (DDHD domain containing 1) This gene is a member of the intracellular phospholipase A1 gene family. The protein encoded by this gene preferentially hydrolyzes phosphatidic acid. It is a cytosolic protein with some mitochondrial localization, and is thought to be involved in the regulation of mitochondrial dynamics. Overexpression of this gene causes fragmentation of the tubular structures in mitochondria, while depletion of the gene results in mitochondrial tubule elongation. Deletion of this gene in male mice caused fertility defects, resulting from disruption in the organization of the mitochondria during spermiogenesis. In humans, mutations in this gene have been associated with hereditary spastic paraplegia (HSP), also known as Strumpell-Lorrain disease, or, familial spastic paraparesis (FSP). This inherited disorder is characterized by progressive weakness and spasticity of the legs. Alternative splicing results in multiple transcript variants encoding different isoforms. [provided by RefSeq, Aug 2015]

DDHD1 (HGNC:):

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.04985681).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DDHD1	NM_001160148.2	c.716A>G	p.Gln239Arg	missense_variant	1/13	ENST00000673822.2	NP_001153620.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DDHD1	ENST00000673822.2	c.716A>G	p.Gln239Arg	missense_variant	1/13		NM_001160148.2	ENSP00000500986.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000400 AC: 1 AN: 250052 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135544

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 SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000886

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461518 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727092

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000180

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000468 Hom.: 0

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Hereditary spastic paraplegia 28 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jul 12, 2022

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. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The arginine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. ClinVar contains an entry for this variant (Variation ID: 1024299). This variant has not been reported in the literature in individuals affected with DDHD1-related conditions. This variant is present in population databases (no rsID available, gnomAD 0.0009%). This sequence change replaces glutamine, which is neutral and polar, with arginine, which is basic and polar, at codon 239 of the DDHD1 protein (p.Gln239Arg). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.061
BayesDel_addAF	Benign	-0.39	T
BayesDel_noAF	Benign	-0.79
CADD	Benign	6.7
DANN	Benign	0.58
DEOGEN2	Benign	0.0079	.;T;.
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.12	N
LIST_S2	Benign	0.75	T;T;T
M_CAP	Benign	0.013	T
MetaRNN	Benign	0.050	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.0	N;N;N
PrimateAI	Benign	0.40	T
PROVEAN	Benign	-0.37	N;N;N
REVEL	Benign	0.045
Sift	Benign	0.53	T;T;T
Sift4G	Benign	0.84	T;T;T
Polyphen		0.0	.;B;B
Vest4		0.037
MutPred		0.26		Loss of glycosylation at S240 (P = 0.0779);Loss of glycosylation at S240 (P = 0.0779);Loss of glycosylation at S240 (P = 0.0779);
MVP		0.043
MPC		0.49
ClinPred		0.012	T
GERP RS		-0.58
Varity_R		0.045
gMVP		0.16

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: rs1189242936; hg19: chr14-53619101;