20-44621103-G-C

Variant names:

• chr20-44621103-G-C
• rs121908718
• NM_000022.4:c.890C>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PM1 PM2 PM5 PP3_Strong

The NM_000022.4(ADA):​c.890C>G​(p.Pro297Arg) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,878 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P297Q) has been classified as Likely pathogenic. The gene ADA is included in the ClinGen Criteria Specification Registry.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ADA NM_000022.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 6.50
• Publications: 0 publications found

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

Specifications for ADA are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PM1: In a hotspot region, there are 5 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000022.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr20-44621103-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 1961.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.987

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000022.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ADA	NM_000022.4	MANE Select	c.890C>G	p.Pro297Arg	missense	Exon 10 of 12	NP_000013.2
	ADA	NM_001322051.2		c.818C>G	p.Pro273Arg	missense	Exon 9 of 11	NP_001308980.1	F5GWI4
	ADA	NM_001322050.2		c.485C>G	p.Pro162Arg	missense	Exon 9 of 11	NP_001308979.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ADA	ENST00000372874.9	TSL:1 MANE Select	c.890C>G	p.Pro297Arg	missense	Exon 10 of 12	ENSP00000361965.4	P00813
	ADA	ENST00000537820.2	TSL:1	c.818C>G	p.Pro273Arg	missense	Exon 9 of 11	ENSP00000441818.1	F5GWI4
	ADA	ENST00000695995.1		c.500C>G	p.Pro167Arg	missense	Exon 7 of 9	ENSP00000512318.1	A0A8Q3SI64

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461878 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727238

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: 53418

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

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111998

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.81
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.50
CADD	Pathogenic	26
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D
Eigen	Uncertain	0.51
Eigen_PC	Uncertain	0.53
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.95	D
M_CAP	Uncertain	0.24	D
MetaRNN	Pathogenic	0.99	D
MetaSVM	Pathogenic	0.89	D
MutationAssessor	Benign	1.5	L
PhyloP100		6.5
PrimateAI	Uncertain	0.61	T
PROVEAN	Pathogenic	-6.4	D
REVEL	Pathogenic	0.84
Sift	Uncertain	0.0020	D
Sift4G	Benign	0.070	T
Polyphen		1.0	D
Vest4		0.92
MutPred		0.95		Loss of ubiquitination at K301 (P = 0.1191)
MVP		0.96
MPC		0.64
ClinPred		1.0	D
GERP RS		5.0
Varity_R		0.93
gMVP		0.98
Mutation Taster		=17/83	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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: rs121908718; hg19: chr20-43249744;