rs886037911

Variant names:

• chr7-128398504-C-A
• rs886037911
• NM_000883.4:c.984G>T

Your query was ambiguous. Multiple possible variants found:

• chr7-128398504-C-A
• chr7-128398504-C-G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PS1 PM1 PM2 PP3_Moderate

The NM_000883.4(IMPDH1):​c.984G>T​(p.Gln328His) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another nucleotide change resulting in the same amino acid substitution has been previously reported as Pathogenic in ClinVar.

• Frequency: Genomes: not found (cov: 32)
• Consequence: IMPDH1 NM_000883.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.41
• Publications: 0 publications found

Genes affected

IMPDH1 (HGNC:6052): (inosine monophosphate dehydrogenase 1) The protein encoded by this gene acts as a homotetramer to regulate cell growth. The encoded protein is an enzyme that catalyzes the synthesis of xanthine monophosphate (XMP) from inosine-5'-monophosphate (IMP). This is the rate-limiting step in the de novo synthesis of guanine nucleotides. Defects in this gene are a cause of retinitis pigmentosa type 10 (RP10). Several transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2008]

IMPDH1 Gene-Disease associations (from GenCC):

• inherited retinal dystrophy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• Leber congenital amaurosis 11

  Inheritance: AD Classification: DEFINITIVE, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), G2P
• retinitis pigmentosa 10

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE Submitted by: Ambry Genetics, G2P, Labcorp Genetics (formerly Invitae)
• Leber congenital amaurosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• retinitis pigmentosa

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

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

• PS1: Transcript NM_000883.4 (IMPDH1) is affected with MISSENSE_VARIANT having same AA change as one Pathogenic present in ClinVar.
• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_000883.4
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.861

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
IMPDH1	NM_000883.4	c.984G>T	p.Gln328His	missense_variant	Exon 10 of 17	ENST00000338791.11	NP_000874.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
IMPDH1	ENST00000338791.11	c.984G>T	p.Gln328His	missense_variant	Exon 10 of 17	2	NM_000883.4	ENSP00000345096.6

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Uncertain:1

Jul 06, 2022

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

ClinVar contains an entry for this variant (Variation ID: 1388602). This sequence change replaces glutamine, which is neutral and polar, with histidine, which is basic and polar, at codon 328 of the IMPDH1 protein (p.Gln328His). This variant is not present in population databases (gnomAD no frequency). This missense change has been observed in individual(s) with Leber congenital amaurosis (PMID: 30029497). Algorithms developed to predict the effect of missense changes on protein structure and function are either unavailable or do not agree on the potential impact of this missense change (SIFT: "Deleterious"; PolyPhen-2: "Probably Damaging"; Align-GVGD: "Class C15"). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.90
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Uncertain	0.12
CADD	Benign	20
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.50	.;.;.;.;D;.;D;.;D
Eigen	Uncertain	0.29
Eigen_PC	Uncertain	0.27
FATHMM_MKL	Pathogenic	0.97	D
LIST_S2	Benign	0.83	T;T;T;T;T;T;.;T;T
M_CAP	Uncertain	0.21	D
MetaRNN	Pathogenic	0.86	D;D;D;D;D;D;D;D;D
MetaSVM	Uncertain	0.19	D
PhyloP100		1.4
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-4.7	D;D;D;D;.;D;D;D;D
REVEL	Pathogenic	0.79
Sift	Uncertain	0.027	D;D;D;D;.;D;D;D;D
Sift4G	Uncertain	0.031	D;D;D;D;D;D;D;D;D
Polyphen		1.0, 0.77	.;.;D;.;.;P;.;.;.
Vest4		0.84
MutPred		0.72		.;.;.;.;.;.;.;.;Gain of catalytic residue at L261 (P = 0.053);
MVP		0.88
MPC		1.4
ClinPred		1.0	D
GERP RS		4.4
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
gMVP		0.83
Mutation Taster		=0/100	disease causing

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: rs886037911; hg19: chr7-128038558;