14-49634423-C-T

Position:

• chr14-49634423-C-T

Variant summary

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

The NM_018139.3(DNAAF2):​c.727G>A​(p.Glu243Lys) 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. 14/21 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: DNAAF2 NM_018139.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.124

Genes affected

DNAAF2 (HGNC:20188): (dynein axonemal assembly factor 2) This gene encodes a highly conserved protein involved in the preassembly of dynein arm complexes which power cilia. These complexes are found in some cilia and are assembled in the cytoplasm prior to transport for cilia formation. Mutations in this gene have been associated with primary ciliary dyskinesia. Multiple transcript variants encoding different isoforms have been found for this gene.[provided by RefSeq, Oct 2009]

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=0.061073244).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DNAAF2	NM_018139.3	c.727G>A	p.Glu243Lys	missense_variant	1/3	ENST00000298292.13	NP_060609.2
DNAAF2	NM_001083908.2	c.727G>A	p.Glu243Lys	missense_variant	1/2		NP_001077377.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DNAAF2	ENST00000298292.13	c.727G>A	p.Glu243Lys	missense_variant	1/3	1	NM_018139.3	ENSP00000298292	P2
DNAAF2	ENST00000406043.3	c.727G>A	p.Glu243Lys	missense_variant	1/2	1		ENSP00000384862	A2

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 88

GnomAD4 genome Cov.: 33

Bravo AF: 0.00000756

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

Nov 11, 2020

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 lysine 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 and their clinical significance is uncertain. This variant has not been reported in the literature in individuals with DNAAF2-related conditions. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate insufficient coverage at this position in the ExAC database. This sequence change replaces glutamic acid with lysine at codon 243 of the DNAAF2 protein (p.Glu243Lys). The glutamic acid residue is moderately conserved and there is a small physicochemical difference between glutamic acid and lysine. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.087
BayesDel_addAF	Benign	-0.25	T
BayesDel_noAF	Benign	-0.60
CADD	Benign	10
DANN	Benign	0.96
DEOGEN2	Benign	0.0016	T;.
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.1
FATHMM_MKL	Benign	0.032	N
LIST_S2	Benign	0.73	T;T
M_CAP	Benign	0.053	D
MetaRNN	Benign	0.061	T;T
MetaSVM	Benign	-0.96	T
MutationAssessor	Benign	0.12	N;N
MutationTaster	Benign	1.0	N;N
PrimateAI	Uncertain	0.68	T
PROVEAN	Benign	-0.68	N;N
REVEL	Benign	0.040
Sift	Benign	0.49	T;T
Sift4G	Benign	0.13	T;T
Polyphen		0.0040	B;B
Vest4		0.14
MutPred		0.49		Gain of catalytic residue at P241 (P = 8e-04);Gain of catalytic residue at P241 (P = 8e-04);
MVP		0.20
MPC		0.80
ClinPred		0.079	T
GERP RS		-0.20
Varity_R		0.075
gMVP		0.41

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: rs727504815; hg19: chr14-50101141;