chr14-53152411-C-A

Position:

• chr14-53152411-C-A

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_001160148.2(DDHD1):​c.688G>T​(p.Asp230Tyr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. 13/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: DDHD1 NM_001160148.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.65

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]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.097759664).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DDHD1	NM_001160148.2	c.688G>T	p.Asp230Tyr	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.688G>T	p.Asp230Tyr	missense_variant	1/13		NM_001160148.2	ENSP00000500986.2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 33

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

Dec 13, 2019

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 are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0"). This variant has not been reported in the literature in individuals with DDHD1-related conditions. This variant is not present in population databases (ExAC no frequency). This sequence change replaces aspartic acid with tyrosine at codon 230 of the DDHD1 protein (p.Asp230Tyr). The aspartic acid residue is weakly conserved and there is a large physicochemical difference between aspartic acid and tyrosine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.090
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	20
DANN	Uncertain	0.99
DEOGEN2	Benign	0.010	.;T;.
Eigen	Benign	-0.54
Eigen_PC	Benign	-0.62
FATHMM_MKL	Benign	0.31	N
LIST_S2	Benign	0.82	T;T;T
M_CAP	Benign	0.043	D
MetaRNN	Benign	0.098	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.69	N;N;N
PrimateAI	Uncertain	0.52	T
PROVEAN	Benign	-1.1	N;N;N
REVEL	Benign	0.18
Sift	Uncertain	0.0050	D;D;D
Sift4G	Uncertain	0.021	D;D;D
Polyphen		0.47, 0.90	.;P;P
Vest4		0.25
MutPred		0.33		Gain of phosphorylation at D230 (P = 0.0019);Gain of phosphorylation at D230 (P = 0.0019);Gain of phosphorylation at D230 (P = 0.0019);
MVP		0.068
MPC		0.55
ClinPred		0.40	T
GERP RS		3.2
Varity_R		0.28
gMVP		0.39

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: rs147832037; hg19: chr14-53619129;