19-55162226-G-C

Position:

• chr19-55162226-G-C

Variant summary

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

The NM_001256715.2(DNAAF3):​c.387C>G​(p.Phe129Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000639 in 1,252,530 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: 𝑓 0.000033 (0 hom., cov: 33)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: DNAAF3 NM_001256715.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.161

Genes affected

DNAAF3 (HGNC:30492): (dynein axonemal assembly factor 3) The protein encoded by this gene is required for the assembly of axonemal inner and outer dynein arms and plays a role in assembling dynein complexes for transport into cilia. Defects in this gene are a cause of primary ciliary dyskinesia type 2 (CILD2). Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, May 2012]

DNAAF3 (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=0.014714748).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DNAAF3	NM_001256715.2	c.387C>G	p.Phe129Leu	missense_variant	5/12	ENST00000524407.7	NP_001243644.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DNAAF3	ENST00000524407.7	c.387C>G	p.Phe129Leu	missense_variant	5/12	1	NM_001256715.2	ENSP00000432046.3

Frequencies

GnomAD3 genomes AF: 0.0000328 AC: 5 AN: 152260 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00103

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD3 exomes AF: 0.0000457 AC: 1 AN: 21874 Hom.: 0 AF XY: 0.0000984 AC XY: 1 AN XY: 10158

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: 0.00234

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000273 AC: 3 AN: 1100152 Hom.: 0 Cov.: 31 AF XY: 0.00000385 AC XY: 2 AN XY: 519856

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: 0.000149

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000328 AC: 5 AN: 152378 Hom.: 0 Cov.: 33 AF XY: 0.0000671 AC XY: 5 AN XY: 74508

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00104

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ExAC AF: 0.0000248 AC: 2

Asia WGS AF: 0.000866 AC: 3 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Jun 19, 2017

In summary, this variant has uncertain impact on DNAAF3 function. The available evidence is currently insufficient to determine its role in disease. Therefore, 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 create or strengthen a splice site, 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 (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. This variant has not been reported in the literature in individuals with a DNAAF3-related disease. While this variant is present in population databases (rs528126745), the frequency information is unreliable, as metrics indicate poor data quality at this position in the ExAC database. This sequence change replaces phenylalanine with leucine at codon 197 of the DNAAF3 protein (p.Phe197Leu). The phenylalanine residue is moderately conserved and there is a small physicochemical difference between phenylalanine and leucine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.78
BayesDel_addAF	Benign	-0.18	T
BayesDel_noAF	Benign	-0.50
CADD	Benign	16
DANN	Uncertain	0.98
DEOGEN2	Benign	0.068	.;T;.;.;T;T
Eigen	Benign	-0.30
Eigen_PC	Benign	-0.34
FATHMM_MKL	Benign	0.69	D
LIST_S2	Benign	0.60	T;T;T;T;T;T
M_CAP	Benign	0.029	D
MetaRNN	Benign	0.015	T;T;T;T;T;T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	1.3	.;L;.;.;.;.
PrimateAI	Pathogenic	0.82	D
PROVEAN	Uncertain	-3.3	D;.;.;D;.;.
REVEL	Benign	0.096
Sift	Benign	0.24	T;.;.;T;.;.
Sift4G	Uncertain	0.030	D;D;D;D;T;.
Polyphen		0.99	.;D;.;.;.;.
Vest4		0.19
MutPred		0.31		.;Loss of catalytic residue at F129 (P = 0.129);.;.;Loss of catalytic residue at F129 (P = 0.129);.;
MVP		0.29
MPC		1.7
ClinPred		0.50	D
GERP RS		0.98
Varity_R		0.054
gMVP		0.40

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs528126745; hg19: chr19-55673594;