17-74289737-G-T

Variant names:

• chr17-74289737-G-T
• rs758109864
• NM_023036.6:c.610+1G>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_023036.6(DNAI2):​c.610+1G>T variant causes a splice donor, intron change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DNAI2 NM_023036.6 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.13
• 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: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, No cryptic splice site detected. Exon removal results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 17-74289737-G-T is Pathogenic according to our data. Variant chr17-74289737-G-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 2829314.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
DNAI2	NM_023036.6	c.610+1G>T		splice_donor_variant, intron_variant	Intron 5 of 13	ENST00000311014.11	NP_075462.3

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
DNAI2	ENST00000311014.11	c.610+1G>T		splice_donor_variant, intron_variant	Intron 5 of 13	1	NM_023036.6	ENSP00000308312.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 35

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Primary ciliary dyskinesia Pathogenic:1

Jan 23, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

In summary, the currently available evidence indicates that the variant is pathogenic, but additional data are needed to prove that conclusively. Therefore, this variant has been classified as Likely Pathogenic. Algorithms developed to predict the effect of sequence changes on RNA splicing suggest that this variant may disrupt the consensus splice site. This variant has not been reported in the literature in individuals affected with DNAI2-related conditions. This variant is not present in population databases (gnomAD no frequency). This sequence change affects a donor splice site in intron 5 of the DNAI2 gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in DNAI2 are known to be pathogenic (PMID: 18950741, 23891469). -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Pathogenic	0.34
CADD	Pathogenic	35
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.95
FATHMM_MKL	Uncertain	0.92	D
PhyloP100		9.1
GERP RS		4.7
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.39		Position offset: -2
DS_DL_spliceai		0.99		Position offset: -1

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

Other links and lift over

dbSNP: rs758109864; hg19: chr17-72285876; COSMIC: COSV56759005;