chr7-128406715-T-G

Variant names:

• chr7-128406715-T-G
• rs28364722
• NM_000883.4:c.255-850A>C

Variant summary

Our verdict is Benign. The variant received -12 ACMG points: 0P and 12B. BP4_Strong BA1

The NM_000883.4(IMPDH1):​c.255-850A>C variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0675 in 152,282 control chromosomes in the GnomAD database, including 737 homozygotes. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.068 (737 hom., cov: 31)
• Consequence: IMPDH1 NM_000883.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.0820
• Publications: 1 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: Benign. The variant received -12 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.81).
• BA1: GnomAd4 highest subpopulation (EAS) allele frequency at 95% confidence interval = 0.224 is higher than 0.05.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000883.4. 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
	IMPDH1	NM_000883.4	MANE Select	c.255-850A>C		intron	N/A	NP_000874.2
	IMPDH1	NM_001102605.2		c.225-850A>C		intron	N/A	NP_001096075.1
	IMPDH1	NM_001142576.2		c.254+2574A>C		intron	N/A	NP_001136048.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	IMPDH1	ENST00000338791.11	TSL:2 MANE Select	c.255-850A>C		intron	N/A	ENSP00000345096.6
	IMPDH1	ENST00000348127.11	TSL:1	c.147-850A>C		intron	N/A	ENSP00000265385.8
	IMPDH1	ENST00000354269.9	TSL:2	c.225-850A>C		intron	N/A	ENSP00000346219.5

Frequencies

GnomAD3 genomes AF: 0.0676 AC: 10283 AN: 152164 Hom.: 735 Cov.: 31

Gnomad AFR AF: 0.0155

Gnomad AMI AF: 0.0164

Gnomad AMR AF: 0.203

Gnomad ASJ AF: 0.0392

Gnomad EAS AF: 0.234

Gnomad SAS AF: 0.0887

Gnomad FIN AF: 0.0708

Gnomad MID AF: 0.0348

Gnomad NFE AF: 0.0571

Gnomad OTH AF: 0.0485

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.0675 AC: 10284 AN: 152282 Hom.: 737 Cov.: 31 AF XY: 0.0727 AC XY: 5411 AN XY: 74452

African (AFR) AF: 0.0154 AC: 641 AN: 41576

American (AMR) AF: 0.203 AC: 3112 AN: 15302

Ashkenazi Jewish (ASJ) AF: 0.0392 AC: 136 AN: 3472

East Asian (EAS) AF: 0.235 AC: 1210 AN: 5156

South Asian (SAS) AF: 0.0876 AC: 423 AN: 4830

European-Finnish (FIN) AF: 0.0708 AC: 751 AN: 10614

Middle Eastern (MID) AF: 0.0408 AC: 12 AN: 294

European-Non Finnish (NFE) AF: 0.0571 AC: 3885 AN: 68020

Other (OTH) AF: 0.0470 AC: 99 AN: 2106

Alfa AF: 0.0580 Hom.: 48

Bravo AF: 0.0746

Asia WGS AF: 0.169 AC: 587 AN: 3478

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.81
CADD	Benign	4.9
DANN	Benign	0.57
PhyloP100		-0.082
Mutation Taster		=100/0	polymorphism (auto)

Splicing

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs28364722; hg19: chr7-128046769;