15-55491208-G-A

Position:

• chr15-55491208-G-A

Variant summary

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

The NM_130810.4(DNAAF4):​c.320C>T​(p.Ala107Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000547 in 1,461,620 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 Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: DNAAF4 NM_130810.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.48

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:43019): (DNAAF4-CCPG1 readthrough (NMD candidate)) This locus represents naturally occurring read-through transcription between the neighboring dyslexia susceptibility 1 candidate 1 (DYX1C1) and cell cycle progression 1 (CCPG1) genes on chromosome 15. The read-through transcript is a candidate for nonsense-mediated mRNA decay (NMD), and is thus unlikely to produce a protein product. [provided by RefSeq, Mar 2011]

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=0.24969527).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DNAAF4	NM_130810.4	c.320C>T	p.Ala107Val	missense_variant	4/10	ENST00000321149.7	NP_570722.2
DNAAF4	NM_001033560.2	c.320C>T	p.Ala107Val	missense_variant	4/9		NP_001028732.1
DNAAF4	NM_001033559.3	c.320C>T	p.Ala107Val	missense_variant	4/9		NP_001028731.1
DNAAF4-CCPG1	NR_037923.1	n.575C>T		non_coding_transcript_exon_variant	3/16

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DNAAF4	ENST00000321149.7	c.320C>T	p.Ala107Val	missense_variant	4/10	1	NM_130810.4	ENSP00000323275.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD3 exomes AF: 0.00000796 AC: 2 AN: 251230 Hom.: 0 AF XY: 0.00000736 AC XY: 1 AN XY: 135784

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: 0.0000176

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000547 AC: 8 AN: 1461620 Hom.: 0 Cov.: 30 AF XY: 0.00000413 AC XY: 3 AN XY: 727098

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: 0.00000630

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 31

EpiCase AF: 0.00

EpiControl AF: 0.0000593

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

Sep 23, 2017

This sequence change replaces alanine with valine at codon 107 of the DYX1C1 protein (p.Ala107Val). The alanine residue is moderately conserved and there is a small physicochemical difference between alanine and valine. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals with DYX1C1-related disease. Algorithms developed to predict the effect of missense changes on protein structure and function (SIFT, PolyPhen-2, Align-GVGD) all suggest that this variant is likely to be tolerated, but these predictions have not been confirmed by published functional studies and their clinical significance is uncertain. 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. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.10
BayesDel_addAF	Benign	-0.15	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	20
DANN	Uncertain	1.0
DEOGEN2	Benign	0.0031	.;.;T;T
Eigen	Uncertain	0.29
Eigen_PC	Uncertain	0.41
FATHMM_MKL	Benign	0.75	D
LIST_S2	Benign	0.83	T;T;T;.
M_CAP	Benign	0.0023	T
MetaRNN	Benign	0.25	T;T;T;T
MetaSVM	Benign	-1.1	T
PrimateAI	Uncertain	0.53	T
PROVEAN	Benign	-1.3	N;N;N;N
REVEL	Benign	0.042
Sift	Benign	0.14	T;T;T;T
Sift4G	Benign	0.38	T;T;T;T
Polyphen		0.99	D;P;B;B
Vest4		0.55
MutPred		0.31		Gain of methylation at K102 (P = 0.1042);Gain of methylation at K102 (P = 0.1042);Gain of methylation at K102 (P = 0.1042);Gain of methylation at K102 (P = 0.1042);
MVP		0.59
MPC		0.065
ClinPred		0.41	T
GERP RS		5.7
Varity_R		0.13
gMVP		0.37

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: rs1258422916; hg19: chr15-55783406;