17-74281887-C-G

Variant names:

• chr17-74281887-C-G
• rs777662498
• NM_023036.6:c.70C>G

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_023036.6(DNAI2):​c.70C>G​(p.Gln24Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000274 in 1,461,854 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 17/22 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. Q24K) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: DNAI2 NM_023036.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.57
• Publications: 0 publications found

Genes affected

DNAI2 (HGNC:18744): (dynein axonemal intermediate chain 2) The protein encoded by this gene belongs to the dynein intermediate chain family, and is part of the dynein complex of respiratory cilia and sperm flagella. Mutations in this gene are associated with primary ciliary dyskinesia type 9. Alternatively spliced transcript variants encoding different isoforms have been noted for this gene. [provided by RefSeq, Mar 2010]

DNAI2 Gene-Disease associations (from GenCC):

• primary ciliary dyskinesia 9

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: PanelApp Australia, Labcorp Genetics (formerly Invitae), ClinGen
• primary ciliary dyskinesia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.11694723).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_023036.6. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DNAI2	NM_023036.6	MANE Select	c.70C>G	p.Gln24Glu	missense	Exon 2 of 14	NP_075462.3
	DNAI2	NM_001353167.2		c.70C>G	p.Gln24Glu	missense	Exon 2 of 15	NP_001340096.1
	DNAI2	NM_001172810.3		c.70C>G	p.Gln24Glu	missense	Exon 2 of 14	NP_001166281.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	DNAI2	ENST00000311014.11	TSL:1 MANE Select	c.70C>G	p.Gln24Glu	missense	Exon 2 of 14	ENSP00000308312.6
	DNAI2	ENST00000579490.5	TSL:1	c.241C>G	p.Gln81Glu	missense	Exon 1 of 13	ENSP00000464197.1
	DNAI2	ENST00000446837.2	TSL:1	c.70C>G	p.Gln24Glu	missense	Exon 1 of 13	ENSP00000400252.2

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000274 AC: 4 AN: 1461854 Hom.: 0 Cov.: 33 AF XY: 0.00000275 AC XY: 2 AN XY: 727228

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53382

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000270 AC: 3 AN: 1112010

Other (OTH) AF: 0.0000166 AC: 1 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia Uncertain:1

Aug 31, 2021

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change replaces glutamine with glutamic acid at codon 24 of the DNAI2 protein (p.Gln24Glu). The glutamine residue is moderately conserved and there is a small physicochemical difference between glutamine and glutamic acid. This variant is not present in population databases (ExAC no frequency). This variant has not been reported in the literature in individuals affected with DNAI2-related conditions. 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. 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 v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.068
BayesDel_addAF	Benign	-0.13	T
BayesDel_noAF	Benign	-0.43
CADD	Benign	19
DANN	Benign	0.54
DEOGEN2	Benign	0.0033	T
Eigen	Benign	-0.28
Eigen_PC	Benign	-0.047
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Benign	0.83	T
M_CAP	Benign	0.0050	T
MetaRNN	Benign	0.12	T
MetaSVM	Benign	-0.99	T
MutationAssessor	Benign	0.34	N
PhyloP100		2.6
PrimateAI	Benign	0.46	T
PROVEAN	Benign	-0.83	N
REVEL	Benign	0.085
Sift	Benign	1.0	T
Sift4G	Benign	1.0	T
Polyphen		0.045	B
Vest4		0.31
MutPred		0.47		Gain of sheet (P = 0.0028)
MVP		0.60
MPC		0.25
ClinPred		0.16	T
GERP RS		5.2
PromoterAI		-0.025	Neutral
Varity_R		0.15
gMVP		0.45
Mutation Taster		=86/14	polymorphism

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

Other links and lift over

dbSNP: rs777662498; hg19: chr17-72278026;