19-44948520-G-C

Variant names:

• chr19-44948520-G-C
• rs1209675341
• NM_000483.5:c.42G>C

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_000483.5(APOC2):​c.42G>C​(p.Leu14Leu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,816 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. L14L) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: APOC2 NM_000483.5 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 2.36
• Publications: 0 publications found

Genes affected

APOC2 (HGNC:609): (apolipoprotein C2) This gene encodes a lipid-binding protein belonging to the apolipoprotein gene family. The protein is secreted in plasma where it is a component of very low density lipoprotein. This protein activates the enzyme lipoprotein lipase, which hydrolyzes triglycerides and thus provides free fatty acids for cells. Mutations in this gene cause hyperlipoproteinemia type IB, characterized by hypertriglyceridemia, xanthomas, and increased risk of pancreatitis and early atherosclerosis. This gene is present in a cluster with other related apolipoprotein genes on chromosome 19. Naturally occurring read-through transcription exists between this gene and the neighboring upstream apolipoprotein C-IV (APOC4) gene. [provided by RefSeq, Mar 2011]

APOC4-APOC2 (HGNC:44426): (APOC4-APOC2 readthrough (NMD candidate)) This locus represents naturally occurring read-through transcription between the neighboring apolipoprotein C-IV (APOC4) and apolipoprotein C-II (APOC2) genes on chromosome 19. The read-through transcript is a candidate for nonsense-mediated mRNA decay (NMD), and is thus unlikely to produce a protein product. [provided by RefSeq, Mar 2011]

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.83).
• BP6: Variant 19-44948520-G-C is Benign according to our data. Variant chr19-44948520-G-C is described in ClinVar as Likely_benign. ClinVar VariationId is 2723717.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=2.36 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000483.5. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APOC2	NM_000483.5	MANE Select	c.42G>C	p.Leu14Leu	synonymous	Exon 2 of 4	NP_000474.2
	APOC4-APOC2	NR_037932.1		n.1249G>C		non_coding_transcript_exon	Exon 4 of 6

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	APOC2	ENST00000252490.7	TSL:2 MANE Select	c.42G>C	p.Leu14Leu	synonymous	Exon 2 of 4	ENSP00000252490.5	P02655
	APOC4-APOC2	ENST00000589057.5	TSL:5	c.273G>C	p.Leu91Leu	synonymous	Exon 3 of 5	ENSP00000468139.1	K7ER74
	APOC2	ENST00000896555.1		c.42G>C	p.Leu14Leu	synonymous	Exon 2 of 4	ENSP00000566614.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461816 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727218

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44722

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.0000252 AC: 1 AN: 39700

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53408

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111962

Other (OTH) AF: 0.00 AC: 0 AN: 60392

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Likely benign

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	-	1	not provided (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.83
CADD	Benign	5.7
DANN	Benign	0.84
PhyloP100		2.4
PromoterAI		0.096	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1

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: rs1209675341; hg19: chr19-45451777;