rs746052951

Positions:

chr20-44622828-C-T

Variant summary

Our verdict is Likely pathogenic. Variant got 6 ACMG points: 6P and 0B. PVS1_ModeratePM2PP5_Moderate

The NM_000022.4(ADA):c.780+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000124 in 1,614,126 control chromosomes in the GnomAD database, with no homozygous occurrence. 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: 𝑓 0.0000066 ( 0 hom., cov: 33)

Exomes 𝑓: 6.8e-7 ( 0 hom. )

Consequence

ADA
NM_000022.4 splice_donor, intron

Scores

Splicing: ADA: 1.000

Clinical Significance

Likely pathogenic criteria provided, single submitter P:1

Conservation

PhyloP100: 6.96

Variant links:

Genes affected

ADA (HGNC:186): (adenosine deaminase) This gene encodes an enzyme that catalyzes the hydrolysis of adenosine to inosine in the purine catabolic pathway. Various mutations have been described for this gene and have been linked to human diseases related to impaired immune function such as severe combined immunodeficiency disease (SCID) which is the result of a deficiency in the ADA enzyme. In ADA-deficient individuals there is a marked depletion of T, B, and NK lymphocytes, and consequently, a lack of both humoral and cellular immunity. Conversely, elevated levels of this enzyme are associated with congenital hemolytic anemia. [provided by RefSeq, Sep 2019]

ADA links:

PKIG (HGNC:9019): (cAMP-dependent protein kinase inhibitor gamma) This gene encodes a member of the protein kinase inhibitor family. Studies of a similar protein in mice suggest that this protein acts as a potent competitive cAMP-dependent protein kinase inhibitor, and is a predominant form of inhibitor in various tissues. The encoded protein may be involved in osteogenesis. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Jul 2013]

PKIG links:

ADA (HGNC:):

ADA links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_pathogenic. Variant got 6 ACMG points.

PVS1

Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.092490844 fraction of the gene. No cryptic splice site detected. Exon removal is inframe change.

PM2

Very rare variant in population databases, with high coverage;

PP5

Variant 20-44622828-C-T is Pathogenic according to our data. Variant chr20-44622828-C-T is described in ClinVar as [Likely_pathogenic]. Clinvar id is 242481.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	Effect	MANE	Protein	UniProt
ADA	NM_000022.4 linkuse as main transcript	c.780+1G>A	splice_donor_variant, intron_variant	ENST00000372874.9	NP_000013.2	P00813A0A0S2Z381
ADA	NM_001322051.2 linkuse as main transcript	c.708+1G>A	splice_donor_variant, intron_variant		NP_001308980.1	F5GWI4
ADA	NM_001322050.2 linkuse as main transcript	c.375+1G>A	splice_donor_variant, intron_variant		NP_001308979.1
ADA	NR_136160.2 linkuse as main transcript	n.872+1G>A	splice_donor_variant, intron_variant

Ensembl

Gene	Transcript	HGVSc	Effect	TSL	MANE	Protein	UniProt
ADA	ENST00000372874.9 linkuse as main transcript	c.780+1G>A	splice_donor_variant, intron_variant	1	NM_000022.4	ENSP00000361965.4	P00813
ADA	ENST00000695995.1 linkuse as main transcript	c.390+1G>A	splice_donor_variant, intron_variant			ENSP00000512318.1	A0A8Q3SI64
ADA	ENST00000695991.1 linkuse as main transcript	c.318+1G>A	splice_donor_variant, intron_variant			ENSP00000512314.1	A0A0S2Z3B9
ADA	ENST00000696038.1 linkuse as main transcript	n.*602+1G>A	splice_donor_variant, intron_variant			ENSP00000512344.1	A0A8Q3SJ57

Frequencies

GnomAD3 genomes

AF:

0.00000657

AC:

AN:

152232

Hom.:

Cov.:

show subpopulations

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:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000147

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251492

Hom.:

AF XY:

0.00000736

AC XY:

AN XY:

135922

show subpopulations

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:

0.00000879

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

6.84e-7

AC:

AN:

1461894

Hom.:

Cov.:

AF XY:

0.00000138

AC XY:

AN XY:

727248

show subpopulations

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:

8.99e-7

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.00000657

AC:

AN:

152232

Hom.:

Cov.:

AF XY:

0.0000134

AC XY:

AN XY:

74382

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000147

Gnomad4 OTH

AF:

0.00

ExAC

AF:

0.00000824

AC:

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Severe combined immunodeficiency, autosomal recessive, T cell-negative, B cell-negative, NK cell-negative, due to adenosine deaminase deficiency

Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 27, 2021

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. ClinVar contains an entry for this variant (Variation ID: 242481). Disruption of this splice site has been observed in individual(s) with atypical severe combined immunodeficiency (PMID: 21664875). This variant is present in population databases (rs746052951, ExAC 0.001%). This sequence change affects a donor splice site in intron 8 of the ADA 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 ADA are known to be pathogenic (PMID: 26255240, 26376800). -

Computational scores

Source: dbNSFP v4.3

Name

Calibrated prediction

Score

Prediction

BayesDel_addAF

Pathogenic

0.63

BayesDel_noAF

Pathogenic

0.29

CADD

Pathogenic

DANN

Uncertain

1.0

Eigen

Pathogenic

1.0

Eigen_PC

Pathogenic

0.84

FATHMM_MKL

Pathogenic

0.98

GERP RS

4.6

Splicing

Name

Calibrated prediction

Score

Prediction

dbscSNV1_ADA

Pathogenic

1.0

dbscSNV1_RF

Pathogenic

0.93

SpliceAI score (max)

0.86

Details are displayed if max score is > 0.2

DS_DL_spliceai

0.86

Position offset: 1

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

Publications

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over