5-35857053-CA-C

Variant names:

• chr5-35857053-CA-C
• NM_002185.5:c.80delA

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_002185.5(IL7R):​c.80delA​(p.Asn27MetfsTer22) variant causes a frameshift, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000139 in 1,438,770 control chromosomes in the GnomAD database, with no homozygous occurrence. 1/1 splice prediction tools predict no significant impact on normal splicing. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: IL7R NM_002185.5 frameshift, splice_region
• Clinical Significance: Pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 2.19
• Publications: 0 publications found

Genes affected

IL7R (HGNC:6024): (interleukin 7 receptor) The protein encoded by this gene is a receptor for interleukin 7 (IL7). The function of this receptor requires the interleukin 2 receptor, gamma chain (IL2RG), which is a common gamma chain shared by the receptors of various cytokines, including interleukins 2, 4, 7, 9, and 15. This protein has been shown to play a critical role in V(D)J recombination during lymphocyte development. Defects in this gene may be associated with severe combined immunodeficiency (SCID). Alternatively spliced transcript variants have been found. [provided by RefSeq, Dec 2015]

IL7R Gene-Disease associations (from GenCC):

• immunodeficiency 104

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae), ClinGen
• Omenn syndrome

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• T-B+ severe combined immunodeficiency due to IL-7Ralpha deficiency

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant located near the start codon (<100nt), not predicted to undergo nonsense mediated mRNA decay. There are 45 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 5-35857053-CA-C is Pathogenic according to our data. Variant chr5-35857053-CA-C is described in ClinVar as [Pathogenic]. Clinvar id is 2763597.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IL7R	NM_002185.5	c.80delA	p.Asn27MetfsTer22	frameshift_variant, splice_region_variant	Exon 1 of 8	ENST00000303115.8	NP_002176.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IL7R	ENST00000303115.8	c.80delA	p.Asn27MetfsTer22	frameshift_variant, splice_region_variant	Exon 1 of 8	1	NM_002185.5	ENSP00000306157.3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000139 AC: 2 AN: 1438770 Hom.: 0 Cov.: 25 AF XY: 0.00000279 AC XY: 2 AN XY: 717392

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 32978

American (AMR) AF: 0.00 AC: 0 AN: 44704

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26016

East Asian (EAS) AF: 0.00 AC: 0 AN: 39594

South Asian (SAS) AF: 0.00 AC: 0 AN: 85874

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52716

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5726

European-Non Finnish (NFE) AF: 0.00000183 AC: 2 AN: 1091524

Other (OTH) AF: 0.00 AC: 0 AN: 59638

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Immunodeficiency 104 Pathogenic:1

Oct 05, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change creates a premature translational stop signal (p.Asn27Metfs*22) in the IL7R gene. It is expected to result in an absent or disrupted protein product. Loss-of-function variants in IL7R are known to be pathogenic (PMID: 21664875, 26123418). This variant is not present in population databases (gnomAD no frequency). This variant has not been reported in the literature in individuals affected with IL7R-related conditions. For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		2.2
Mutation Taster		=7/193	disease causing (fs/PTC)

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

hg19: chr5-35857155;