2-43886706-G-A

Position:

• chr2-43886706-G-A

Variant summary

Our verdict is Likely benign. Variant got -3 ACMG points: 2P and 5B. PM2 BP4_Strong BS1_Supporting

The NM_133259.4(LRPPRC):​c.*1894C>T variant causes a 3 prime UTR change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000282 in 152,238 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.00028 (1 hom., cov: 32)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: LRPPRC NM_133259.4 3_prime_UTR
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: -0.0920

Genes affected

LRPPRC (HGNC:15714): (leucine rich pentatricopeptide repeat containing) This gene encodes a leucine-rich protein that has multiple pentatricopeptide repeats (PPR). The precise role of this protein is unknown but studies suggest it may play a role in cytoskeletal organization, vesicular transport, or in transcriptional regulation of both nuclear and mitochondrial genes. The protein localizes primarily to mitochondria and is predicted to have an N-terminal mitochondrial targeting sequence. Mutations in this gene are associated with the French-Canadian type of Leigh syndrome. [provided by RefSeq, Mar 2012]

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=-0.84).
• BS1: Variant frequency is greater than expected in population sas. gnomad4 allele frequency = 0.000282 (43/152238) while in subpopulation SAS AF= 0.00643 (31/4818). AF 95% confidence interval is 0.00466. There are 1 homozygotes in gnomad4. There are 25 alleles in male gnomad4 subpopulation. Median coverage is 32. This position pass quality control queck. Existence of Clinvar submissions makes me limit the strength of this signal to Supporting

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
LRPPRC	NM_133259.4	c.*1894C>T		3_prime_UTR_variant	38/38	ENST00000260665.12
LRPPRC	XM_006711915.3	c.*1894C>T		3_prime_UTR_variant	38/38
LRPPRC	XM_047442809.1	c.*1894C>T		3_prime_UTR_variant	38/38

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
LRPPRC	ENST00000260665.12	c.*1894C>T		3_prime_UTR_variant	38/38	1	NM_133259.4	P3
LRPPRC	ENST00000684454.1	n.9943C>T		non_coding_transcript_exon_variant	7/7
LRPPRC	ENST00000682612.1	c.*2046C>T		3_prime_UTR_variant, NMD_transcript_variant	8/8

Frequencies

GnomAD3 genomes AF: 0.000283 AC: 43 AN: 152120 Hom.: 1 Cov.: 32

Gnomad AFR AF: 0.000266

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.00

Gnomad SAS AF: 0.00643

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 16 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 8

Gnomad4 AFR exome AF: 0.00

Gnomad4 NFE exome AF: 0.00

GnomAD4 genome AF: 0.000282 AC: 43 AN: 152238 Hom.: 1 Cov.: 32 AF XY: 0.000336 AC XY: 25 AN XY: 74432

Gnomad4 AFR AF: 0.000265

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00643

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.0000147

Gnomad4 OTH AF: 0.00

Alfa AF: 0.000142 Hom.: 0

Bravo AF: 0.000106

Asia WGS AF: 0.00375 AC: 13 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital lactic acidosis, Saguenay-Lac-Saint-Jean type Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Illumina Laboratory Services, Illumina

Jan 13, 2018

This variant was observed in the ICSL laboratory as part of a predisposition screen in an ostensibly healthy population. It had not been previously curated by ICSL or reported in the Human Gene Mutation Database (HGMD: prior to June 1st, 2018), and was therefore a candidate for classification through an automated scoring system. Utilizing variant allele frequency, disease prevalence and penetrance estimates, and inheritance mode, an automated score was calculated to assess if this variant is too frequent to cause the disease. Based on the score, this variant could not be ruled out of causing disease and therefore its association with disease required further investigation. A literature search was performed for the gene, cDNA change, and amino acid change (if applicable). No publications were found based on this search. This variant was therefore classified as a variant of unknown significance for this disease. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.84
CADD	Benign	1.3
DANN	Benign	0.70

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: rs563480210; hg19: chr2-44113845;