7-44539581-G-T

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_001101648.2(NPC1L1):c.816C>A(p.Leu272=) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. L272L) has been classified as Benign.

• Frequency: Genomes: not found (cov: 33)
• Consequence: NPC1L1 NM_001101648.2 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.15

Genes affected

NPC1L1 (HGNC:7898): (NPC1 like intracellular cholesterol transporter 1) The protein encoded by this gene is a multi-pass membrane protein. It contains a conserved N-terminal Niemann-Pick C1 (NPC1) domain and a putative sterol-sensing domain (SSD) which includes a YQRL motif functioning as a plasma membrane to trans-Golgi network transport signal in other proteins. This protein takes up free cholesterol into cells through vesicular endocytosis and plays a critical role in the absorption of intestinal cholesterol. It also has the ability to transport alpha-tocopherol (vitamin E). The drug ezetimibe targets this protein and inhibits the absorption of intestinal cholesterol and alpha-tocopherol. In addition, this protein may play a critical role in regulating lipid metabolism. Polymorphic variations in this gene are associated with plasma total cholesterol and low-density lipoprotein cholesterol (LDL-C) levels and coronary heart disease (CHD) risk. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Oct 2009]

ACMG classification

Verdict is Likely_benign. Variant got -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.76).
• BP7: Synonymous conserved (PhyloP=1.15 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
NPC1L1	NM_001101648.2	c.816C>A	p.Leu272=	synonymous_variant	2/19	ENST00000381160.8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
NPC1L1	ENST00000381160.8	c.816C>A	p.Leu272=	synonymous_variant	2/19	1	NM_001101648.2	P1
NPC1L1	ENST00000289547.8	c.816C>A	p.Leu272=	synonymous_variant	2/20	1
NPC1L1	ENST00000546276.5	c.816C>A	p.Leu272=	synonymous_variant	2/18	1
NPC1L1	ENST00000423141.1	c.816C>A	p.Leu272=	synonymous_variant	2/7	1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Cov.: 40

GnomAD4 genome Cov.: 33

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.76
Cadd	Benign	1.3
Dann	Benign	0.42

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: rs2072183; hg19: chr7-44579180;