15-55435056-T-C

Position:

• chr15-55435056-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP3_Moderate

The NM_130810.4(DNAAF4):​c.896A>G​(p.Lys299Arg) variant causes a missense, splice region 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. 13/22 in silico tools predict a benign outcome for this variant. 1/1 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 33)
• Consequence: DNAAF4 NM_130810.4 missense, splice_region
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.33

Genes affected

DNAAF4 (HGNC:21493): (dynein axonemal assembly factor 4) This gene encodes a tetratricopeptide repeat domain-containing protein. The encoded protein interacts with estrogen receptors and the heat shock proteins, Hsp70 and Hsp90. An homologous protein in rat has been shown to function in neuronal migration in the developing neocortex. A chromosomal translocation involving this gene is associated with a susceptibility to developmental dyslexia. Mutations in this gene are associated with deficits in reading and spelling. Alternative splicing results in multiple transcript variants. Read-through transcription also exists between this gene and the downstream cell cycle progression 1 (CCPG1) gene. [provided by RefSeq, Mar 2011]

DNAAF4-CCPG1 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: Splicing scoreres supports a deletorius effect: Scorers claiming Pathogenic: max_spliceai. No scorers claiming Uncertain. No scorers claiming Benign.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DNAAF4	NM_130810.4	c.896A>G	p.Lys299Arg	missense_variant, splice_region_variant	8/10	ENST00000321149.7	NP_570722.2
DNAAF4-CCPG1	NR_037923.1	n.1151A>G		splice_region_variant, non_coding_transcript_exon_variant	7/16
DNAAF4	NM_001033560.2	c.896A>G	p.Lys299Arg	missense_variant, splice_region_variant	8/9		NP_001028732.1
DNAAF4	NM_001033559.3	c.896A>G	p.Lys299Arg	missense_variant, splice_region_variant	8/9		NP_001028731.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DNAAF4	ENST00000321149.7	c.896A>G	p.Lys299Arg	missense_variant, splice_region_variant	8/10	1	NM_130810.4	ENSP00000323275	P1

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

not provided Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 05, 2016

In summary, this variant is a novel missense change with uncertain impact on protein function. It has been classified as a Variant of Uncertain Significance. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may alter RNA splicing, but this prediction has not been confirmed by published transcriptional studies. 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, suggesting that this missense change does not adversely affect protein function. These predictions have not been confirmed by published functional studies. This variant is not present in population databases (ExAC no frequency) and has not been reported in the literature in individuals with a DYX1C1-related disease. This sequence change replaces lysine with arginine at codon 299 of the DYX1C1 protein (p.Lys299Arg). The lysine residue is highly conserved and there is a small physicochemical difference between lysine and arginine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.088
BayesDel_addAF	Benign	-0.057	T
BayesDel_noAF	Benign	-0.32
CADD	Benign	22
DANN	Uncertain	1.0
DEOGEN2	Benign	0.0023	.;.;T;T
Eigen	Benign	0.10
Eigen_PC	Benign	0.21
FATHMM_MKL	Uncertain	0.87	D
LIST_S2	Benign	0.81	T;T;T;.
M_CAP	Benign	0.012	T
MetaRNN	Benign	0.29	T;T;T;T
MetaSVM	Benign	-0.97	T
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Benign	0.44	T
PROVEAN	Benign	-1.2	N;N;N;N
REVEL	Benign	0.070
Sift	Benign	0.036	D;D;D;D
Sift4G	Benign	0.13	T;T;T;T
Polyphen		0.79	P;P;B;B
Vest4		0.28
MutPred		0.38		Loss of ubiquitination at K299 (P = 0.021);Loss of ubiquitination at K299 (P = 0.021);Loss of ubiquitination at K299 (P = 0.021);Loss of ubiquitination at K299 (P = 0.021);
MVP		0.68
MPC		0.052
ClinPred		0.88	D
GERP RS		4.0
Varity_R		0.11
gMVP		0.37

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.82		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.82		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs1060503096; hg19: chr15-55727254;