20-44625602-G-C

Variant names:

• chr20-44625602-G-C
• rs121908733
• NM_000022.4:c.445C>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.445C>G​(p.Arg149Gly) variant causes a missense change. The variant allele was found at a frequency of 0.000000696 in 1,436,750 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. R149W) has been classified as Likely pathogenic.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 7.0e-7 (0 hom.)
• Consequence: ADA NM_000022.4 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 4.53
• Publications: 7 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]

ADA Gene-Disease associations (from GenCC):

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

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), G2P, Myriad Women’s Health, Orphanet
• Omenn syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 1 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 chr20-44625602-G-A is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 68264.Status of the report is reviewed_by_expert_panel, 3 stars.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.964

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

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ADA	NM_000022.4	MANE Select	c.445C>G	p.Arg149Gly	missense	Exon 5 of 12	NP_000013.2
	ADA	NM_001322051.2		c.445C>G	p.Arg149Gly	missense	Exon 5 of 11	NP_001308980.1
	ADA	NR_136160.2		n.537C>G		non_coding_transcript_exon	Exon 5 of 11

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ADA	ENST00000372874.9	TSL:1 MANE Select	c.445C>G	p.Arg149Gly	missense	Exon 5 of 12	ENSP00000361965.4
	ADA	ENST00000537820.2	TSL:1	c.445C>G	p.Arg149Gly	missense	Exon 5 of 11	ENSP00000441818.1
	ADA	ENST00000696038.1		n.*191C>G		non_coding_transcript_exon	Exon 5 of 9	ENSP00000512344.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000473 AC: 1 AN: 211354 AF XY: 0.00000880

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 FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.96e-7 AC: 1 AN: 1436750 Hom.: 0 Cov.: 31 AF XY: 0.00000140 AC XY: 1 AN XY: 712326

African (AFR) AF: 0.00 AC: 0 AN: 33092

American (AMR) AF: 0.00 AC: 0 AN: 41494

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25508

East Asian (EAS) AF: 0.00 AC: 0 AN: 38690

South Asian (SAS) AF: 0.0000121 AC: 1 AN: 82496

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 51362

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4830

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1099916

Other (OTH) AF: 0.00 AC: 0 AN: 59362

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.40
BayesDel_addAF	Pathogenic	0.40	D
BayesDel_noAF	Pathogenic	0.45
CADD	Uncertain	25
DANN	Uncertain	1.0
DEOGEN2	Pathogenic	0.95	D
Eigen	Uncertain	0.50
Eigen_PC	Uncertain	0.48
FATHMM_MKL	Uncertain	0.92	D
LIST_S2	Pathogenic	0.97	D
M_CAP	Uncertain	0.25	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	0.81	D
MutationAssessor	Benign	1.9	L
PhyloP100		4.5
PrimateAI	Uncertain	0.56	T
PROVEAN	Pathogenic	-5.9	D
REVEL	Pathogenic	0.83
Sift	Uncertain	0.0020	D
Sift4G	Uncertain	0.057	T
Polyphen		1.0	D
Vest4		0.94
MutPred		0.79		Loss of MoRF binding (P = 0.0097)
MVP		0.94
MPC		0.71
ClinPred		0.97	D
GERP RS		3.5
Varity_R		0.92
gMVP		0.93
Mutation Taster		=21/79	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs121908733; hg19: chr20-43254243;