22-23573294-T-A

Position:

• chr22-23573294-T-A

Variant summary

Our verdict is Uncertain significance. Variant got 2 ACMG points: 2P and 0B. PM2

The NM_020070.4(IGLL1):​c.614A>T​(p.Lys205Met) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,876 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: IGLL1 NM_020070.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 2.73

Genes affected

IGLL1 (HGNC:5870): (immunoglobulin lambda like polypeptide 1) The preB cell receptor is found on the surface of proB and preB cells, where it is involved in transduction of signals for cellular proliferation, differentiation from the proB cell to the preB cell stage, allelic exclusion at the Ig heavy chain gene locus, and promotion of Ig light chain gene rearrangements. The preB cell receptor is composed of a membrane-bound Ig mu heavy chain in association with a heterodimeric surrogate light chain. This gene encodes one of the surrogate light chain subunits and is a member of the immunoglobulin gene superfamily. This gene does not undergo rearrangement. Mutations in this gene can result in B cell deficiency and agammaglobulinemia, an autosomal recessive disease in which few or no gamma globulins or antibodies are made. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

ENSG00000224277 (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
IGLL1	NM_020070.4	c.614A>T	p.Lys205Met	missense_variant	3/3	ENST00000330377.3	NP_064455.1
IGLL1	NM_001369906.1	c.617A>T	p.Lys206Met	missense_variant	3/3		NP_001356835.1
IGLL1	NM_152855.3	c.*243A>T		3_prime_UTR_variant	2/2		NP_690594.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
IGLL1	ENST00000330377.3	c.614A>T	p.Lys205Met	missense_variant	3/3	1	NM_020070.4	ENSP00000329312.2
IGLL1	ENST00000249053	c.*243A>T		3_prime_UTR_variant	2/2	1		ENSP00000249053.3
ENSG00000224277	ENST00000458318.2	n.391-171T>A		intron_variant		3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461876 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 727240

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Aug 16, 2022

The c.614A>T (p.K205M) alteration is located in exon 3 (coding exon 3) of the IGLL1 gene. This alteration results from a A to T substitution at nucleotide position 614, causing the lysine (K) at amino acid position 205 to be replaced by a methionine (M). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Uncertain	0.38
BayesDel_addAF	Benign	-0.085	T
BayesDel_noAF	Benign	-0.36
CADD	Benign	20
DANN	Uncertain	0.99
DEOGEN2	Uncertain	0.80	D
Eigen	Uncertain	0.26
Eigen_PC	Benign	0.028
FATHMM_MKL	Benign	0.53	D
LIST_S2	Uncertain	0.96	D
M_CAP	Benign	0.0094	T
MetaRNN	Uncertain	0.67	D
MetaSVM	Benign	-1.1	T
MutationAssessor	Pathogenic	4.0	H
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-5.0	D
REVEL	Benign	0.10
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.46
MutPred		0.60		Loss of ubiquitination at K205 (P = 0.0041);
MVP		0.41
MPC		0.39
ClinPred		0.99	D
GERP RS		2.5
Varity_R		0.76
gMVP		0.64

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: rs1924868488; hg19: chr22-23915481;