NM_000206.3:c.677G>A

Variant names:

• chrX-71109308-C-T
• rs869320660
• NM_000206.3:c.677G>A

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PM1_Strong PM5 PS3_Supporting PM2_Supporting PP4_Moderate PS4

This summary comes from the ClinGen Evidence Repository: The NM_000206.3:c.677G>A variant in IL2RG is a missense variant predicted to cause substitution of arginine by histidine at amino acid 226 (p.Arg226His). The variant has been observed in at least 9 probands with SCID/Ommen Syndrome (PMIDs 7668284, 9058718, 17598841, 21184155) (PS4). Among these probands, one presented with symptoms reminiscent of Omenn syndrome. The proband exhibited a T-B-NK+ lymphocyte profile. CD132 was absent in every lymphocyte subpopulation, and the NK cells isolated from the patient did not respond to IL-2 stimulation (PMID 17598841) (PP4). The variant is absent from gnomAD v4.0 (PM2_Supporting). The variant affects CpG dinucleotides at c.677G, which is defined as a mutational hotspot by the ClinGen SCID VCEP (PMID 7668284) (PM1_Strong). Surface expression of the IL-2 receptor gamma chain in patient B cells showed that the variant causes decreased surface localization of the protein, indicating that this variant impacts protein function (PMID 9058718)(PS3_Supporting). In addition, another missense variant c.676C>T, p.Arg226Cys (ClinVar Variation ID 225195) in the same codon has been classified as pathogenic for SCID by the ClinGen SCID VCEP (PM5). In summary, this variant meets the criteria to be classified as pathogenic for SCID. ACMG/AMP criteria applied, as specified by the ClinGen SCID-VCEP: PM1_Strong, PS4_Strong, PM5, PP4_Moderate, PM2_Supporting, PS3_Supporting. (VCEP specifications version 1.0) LINK:https://erepo.genome.network/evrepo/ui/classification/CA358793/MONDO:0010315/129

• Frequency: Genomes: not found (cov: 23)
• Consequence: IL2RG NM_000206.3 missense
• Clinical Significance: Pathogenic reviewed by expert panel P:3
• Conservation: PhyloP100: 2.80
• Publications: 12 publications found

Genes affected

IL2RG (HGNC:6010): (interleukin 2 receptor subunit gamma) The protein encoded by this gene is an important signaling component of many interleukin receptors, including those of interleukin -2, -4, -7 and -21, and is thus referred to as the common gamma chain. Mutations in this gene cause X-linked severe combined immunodeficiency (XSCID), as well as X-linked combined immunodeficiency (XCID), a less severe immunodeficiency disorder. [provided by RefSeq, Mar 2010]

IL2RG Gene-Disease associations (from GenCC):

• T-B+ severe combined immunodeficiency due to gamma chain deficiency

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

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000285171 (HGNC:):

ACMG classification

Specifications for IL2RG are available in the ClinGen Criteria Specification Registry and recommended for reference when assigning criteria.

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PS3: For more information check the summary or visit ClinGen Evidence Repository.
• PS4: For more information check the summary or visit ClinGen Evidence Repository.
• PM1: For more information check the summary or visit ClinGen Evidence Repository.
• PM2: For more information check the summary or visit ClinGen Evidence Repository.
• PM5: For more information check the summary or visit ClinGen Evidence Repository.
• PP4: For more information check the summary or visit ClinGen Evidence Repository.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000206.3. 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
	IL2RG	NM_000206.3	MANE Select	c.677G>A	p.Arg226His	missense	Exon 5 of 8	NP_000197.1	P31785-1
	IL2RG	NM_001438870.1		c.677G>A	p.Arg226His	missense	Exon 5 of 7	NP_001425799.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IL2RG	ENST00000374202.7	TSL:1 MANE Select	c.677G>A	p.Arg226His	missense	Exon 5 of 8	ENSP00000363318.3	P31785-1
	ENSG00000285171	ENST00000646505.1		n.677G>A		non_coding_transcript_exon	Exon 5 of 12	ENSP00000496673.1	A0A2R8YE73
	IL2RG	ENST00000482750.6	TSL:5	c.677G>A	p.Arg226His	missense	Exon 5 of 7	ENSP00000421262.2	H0Y8J6

Frequencies

GnomAD3 genomes Cov.: 23

GnomAD4 exome Cov.: 30

GnomAD4 genome Cov.: 23

Alfa AF: 0.00 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: reviewed by expert panel

Pathogenic	VUS	Benign	Condition
2	-	-	X-linked severe combined immunodeficiency (2)
1	-	-	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.25
BayesDel_addAF	Pathogenic	0.48	D
BayesDel_noAF	Pathogenic	0.45
CADD	Pathogenic	28
DANN	Pathogenic	1.0
DEOGEN2	Pathogenic	0.89	D
FATHMM_MKL	Benign	0.66	D
LIST_S2	Uncertain	0.91	D
M_CAP	Pathogenic	0.82	D
MetaRNN	Pathogenic	0.98	D
MetaSVM	Pathogenic	0.92	D
MutationAssessor	Uncertain	2.4	M
PhyloP100		2.8
PrimateAI	Uncertain	0.54	T
PROVEAN	Uncertain	-3.8	D
REVEL	Pathogenic	0.65
Sift	Uncertain	0.0050	D
Sift4G	Uncertain	0.0060	D
Polyphen		1.0	D
Vest4		0.58
MutPred		0.90		Loss of methylation at R226 (P = 0.016)
MVP		0.99
MPC		1.7
ClinPred		0.99	D
GERP RS		4.7
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Varity_R		0.73
gMVP		0.76
Mutation Taster		=29/71	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs869320660; hg19: chrX-70329158; COSMIC: COSV52149638; COSMIC: COSV52149638;