5-75358757-T-C

Position:

• chr5-75358757-T-C

Variant summary

Our verdict is Uncertain significance. Variant got 4 ACMG points: 4P and 0B. PM2 PP2 PP3

The NM_000859.3(HMGCR):​c.2087T>C​(p.Ile696Thr) variant causes a missense change. The variant allele was found at a frequency of 0.000000684 in 1,461,576 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: HMGCR NM_000859.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 6.27

Genes affected

HMGCR (HGNC:5006): (3-hydroxy-3-methylglutaryl-CoA reductase) HMG-CoA reductase is the rate-limiting enzyme for cholesterol synthesis and is regulated via a negative feedback mechanism mediated by sterols and non-sterol metabolites derived from mevalonate, the product of the reaction catalyzed by reductase. Normally in mammalian cells this enzyme is suppressed by cholesterol derived from the internalization and degradation of low density lipoprotein (LDL) via the LDL receptor. Competitive inhibitors of the reductase induce the expression of LDL receptors in the liver, which in turn increases the catabolism of plasma LDL and lowers the plasma concentration of cholesterol, an important determinant of atherosclerosis. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Aug 2008]

CERT1 (HGNC:2205): (ceramide transporter 1) This gene encodes a kinase that specifically phosphorylates the N-terminal region of the non-collagenous domain of the alpha 3 chain of type IV collagen, known as the Goodpasture antigen. Goodpasture disease is the result of an autoimmune response directed at this antigen. One isoform of this protein is also involved in ceramide intracellular transport. Three transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

HMGCR (HGNC:):

ACMG classification

Verdict is Uncertain_significance. Variant got 4 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), HMGCR. . Gene score misZ 3.7591 (greater than the threshold 3.09). Trascript score misZ 4.2252 (greater than threshold 3.09). GenCC has associacion of gene with muscular dystrophy, limb-girdle, autosomal recessive 28.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.811

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
HMGCR	NM_000859.3	c.2087T>C	p.Ile696Thr	missense_variant	16/20	ENST00000287936.9	NP_000850.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
HMGCR	ENST00000287936.9	c.2087T>C	p.Ile696Thr	missense_variant	16/20	1	NM_000859.3	ENSP00000287936.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461576 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727084

Gnomad4 AFR exome AF: 0.0000299

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: 0.00

GnomAD4 genome Cov.: 32

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Oct 01, 2024

The c.2087T>C (p.I696T) alteration is located in exon 16 (coding exon 15) of the HMGCR gene. This alteration results from a T to C substitution at nucleotide position 2087, causing the isoleucine (I) at amino acid position 696 to be replaced by a threonine (T). 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	Pathogenic	0.71
BayesDel_addAF	Pathogenic	0.24	D
BayesDel_noAF	Uncertain	0.10
CADD	Pathogenic	28
DANN	Uncertain	1.0
DEOGEN2	Uncertain	0.47	T;T;.;.
Eigen	Uncertain	0.52
Eigen_PC	Uncertain	0.55
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.98	.;D;D;D
M_CAP	Benign	0.062	D
MetaRNN	Pathogenic	0.81	D;D;D;D
MetaSVM	Uncertain	0.011	D
MutationAssessor	Uncertain	2.6	M;M;.;.
PrimateAI	Uncertain	0.76	T
PROVEAN	Uncertain	-3.6	D;D;D;D
REVEL	Uncertain	0.50
Sift	Uncertain	0.0010	D;D;D;D
Sift4G	Uncertain	0.0030	D;D;D;D
Polyphen		0.29	B;B;B;.
Vest4		0.77
MutPred		0.71		Gain of disorder (P = 0.0692);Gain of disorder (P = 0.0692);.;.;
MVP		0.68
MPC		1.5
ClinPred		0.95	D
GERP RS		5.8
Varity_R		0.86
gMVP		0.98

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.050		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: rs1760687566; hg19: chr5-74654582;