20-44619682-G-A

Position:

• chr20-44619682-G-A

Variant summary

Our verdict is Benign. Variant got -9 ACMG points: 0P and 9B. BP4_Strong BS1_Supporting BS2

The NM_000022.4(ADA):​c.*152C>T variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000218 in 1,002,394 control chromosomes in the GnomAD database, including 2 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00016 (0 hom., cov: 33)
  • Exomes 𝑓: 0.00023 (2 hom.)
• Consequence: ADA NM_000022.4 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -1.20

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]

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]

ACMG classification

Verdict is Benign. Variant got -9 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.85).
• BS1: Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000158 (24/152356) while in subpopulation SAS AF= 0.00435 (21/4828). AF 95% confidence interval is 0.00291. There are 0 homozygotes in gnomad4. There are 18 alleles in male gnomad4 subpopulation. Median coverage is 33. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting
• BS2: High Homozygotes in GnomAdExome4 at 2 AR gene

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
ADA	NM_000022.4	c.*152C>T		3_prime_UTR_variant	12/12	ENST00000372874.9
ADA	NM_001322050.2	c.*152C>T		3_prime_UTR_variant	11/11
ADA	NM_001322051.2	c.*152C>T		3_prime_UTR_variant	11/11
ADA	NR_136160.2	n.1271C>T		non_coding_transcript_exon_variant	11/11

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
ADA	ENST00000372874.9	c.*152C>T		3_prime_UTR_variant	12/12	1	NM_000022.4	P4

Frequencies

GnomAD3 genomes AF: 0.000158 AC: 24 AN: 152238 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.000196

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00435

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.000229 AC: 195 AN: 850038 Hom.: 2 Cov.: 11 AF XY: 0.000337 AC XY: 149 AN XY: 441874

Gnomad4 AFR exome AF: 0.0000937

Gnomad4 AMR exome AF: 0.0000534

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00259

Gnomad4 FIN exome AF: 0.0000203

Gnomad4 NFE exome AF: 0.00000350

Gnomad4 OTH exome AF: 0.000151

GnomAD4 genome AF: 0.000158 AC: 24 AN: 152356 Hom.: 0 Cov.: 33 AF XY: 0.000242 AC XY: 18 AN XY: 74496

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.000196

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00435

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

Bravo AF: 0.0000604

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Severe combined immunodeficiency, autosomal recessive, T cell-negative, B cell-negative, NK cell-negative, due to adenosine deaminase deficiency Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.85
CADD	Benign	0.52
DANN	Benign	0.82
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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: rs560858565; hg19: chr20-43248323; COSMIC: COSV63068903; COSMIC: COSV63068903;