Genetic Variant CHMP1A:c.*13G>A (chr16-89646053-C-T) – ACMG Classification: Likely_benign (-6 pts)

Variant summary

Our verdict is Likely benign. Variant got -6 ACMG points: 2P and 8B. PM2BP4_StrongBS1

The NM_001083314.4(CHMP1A):c.584G>A(p.Arg195Gln) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000705 in 1,418,366 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 5/5 in silico tools predict a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

Frequency

Genomes: not found (cov: 33)

Exomes 𝑓: 0.0000071 ( 0 hom. )

Consequence

CHMP1A
NM_001083314.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -2.43

Variant links:

Genes affected

CHMP1A (HGNC:8740): (charged multivesicular body protein 1A) This gene encodes a member of the CHMP/Chmp family of proteins which are involved in multivesicular body sorting of proteins to the interiors of lysosomes. The initial prediction of the protein sequence encoded by this gene suggested that the encoded protein was a metallopeptidase. The nomenclature has been updated recently to reflect the correct biological function of this encoded protein. Several transcripts encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2012]

CHMP1A links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -6 ACMG points.

PM2

Very rare variant in population databases, with high coverage;

BP4

Computational evidence support a benign effect (BayesDel_noAF=-0.79).

BS1

Variant frequency is greater than expected in population mid. gnomad4_exome allele frequency = 0.00000705 (10/1418366) while in subpopulation MID AF= 0.000399 (2/5016). AF 95% confidence interval is 0.0000704. There are 0 homozygotes in gnomad4_exome. There are 6 alleles in male gnomad4_exome subpopulation. Median coverage is 31. This position pass quality control queck.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CHMP1A	NM_002768.5 link	c.*13G>A		3_prime_UTR_variant	Exon 7 of 7	ENST00000397901.8	NP_002759.2	Q9HD42-1
CHMP1A	NM_001083314.4 link	c.584G>A	p.Arg195Gln	missense_variant	Exon 6 of 6		NP_001076783.1
CHMP1A	XM_047434195.1 link	c.*13G>A		3_prime_UTR_variant	Exon 7 of 7		XP_047290151.1
CHMP1A	NR_046418.3 link	n.892G>A		non_coding_transcript_exon_variant	Exon 7 of 7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CHMP1A	ENST00000397901 link	c.*13G>A		3_prime_UTR_variant	Exon 7 of 7	1	NM_002768.5	ENSP00000380998.3		Q9HD42-1

Frequencies

GnomAD3 genomes

Cov.:

GnomAD3 exomes

AF:

0.00000932

AC:

AN:

214628

Hom.:

AF XY:

0.00000858

AC XY:

AN XY:

116540

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.0000709

Gnomad ASJ exome

AF:

0.00

Gnomad EAS exome

AF:

0.00

Gnomad SAS exome

AF:

0.00

Gnomad FIN exome

AF:

0.00

Gnomad NFE exome

AF:

0.00

Gnomad OTH exome

AF:

0.00

GnomAD4 exome

AF:

0.00000705

AC:

AN:

1418366

Hom.:

Cov.:

AF XY:

0.00000856

AC XY:

AN XY:

701246

show subpopulations

Gnomad4 AFR exome

AF:

0.00

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:

0.00000550

Gnomad4 OTH exome

AF:

0.0000343

GnomAD4 genome

Cov.:

Bravo

AF:

0.00000378

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

Inborn genetic diseases

Uncertain:1

Jan 10, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.584G>A (p.R195Q) alteration is located in exon 6 (coding exon 6) of the CHMP1A gene. This alteration results from a G to A substitution at nucleotide position 584, causing the arginine (R) at amino acid position 195 to be replaced by a glutamine (Q). 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

BayesDel_noAF

Benign

-0.79

CADD

Benign

0.83

DANN

Benign

0.80

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.0

Splicing

Name

Calibrated prediction

Score

Prediction

SpliceAI score (max)

0.010

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

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over