18-74556395-C-A

Position:

• chr18-74556395-C-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_032649.6(CNDP1):​c.82C>A​(p.Pro28Thr) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,786 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 14/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CNDP1 NM_032649.6 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.0140

Genes affected

CNDP1 (HGNC:20675): (carnosine dipeptidase 1) This gene encodes a member of the M20 metalloprotease family. The encoded protein is specifically expressed in the brain, is a homodimeric dipeptidase which was identified as human carnosinase. This gene contains trinucleotide (CTG) repeat length polymorphism in the coding region. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.055824608).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
CNDP1	NM_032649.6	c.82C>A	p.Pro28Thr	missense_variant	2/12	ENST00000358821.8	NP_116038.4

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
CNDP1	ENST00000358821.8	c.82C>A	p.Pro28Thr	missense_variant	2/12	1	NM_032649.6	ENSP00000351682.3
CNDP1	ENST00000582365.1	c.25-2928C>A		intron_variant		5		ENSP00000462096.1
CNDP1	ENST00000585136.1	n.247C>A		non_coding_transcript_exon_variant	2/5	3

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461786 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727196

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: 0.00

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome Cov.: 33

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 07, 2024

The c.82C>A (p.P28T) alteration is located in exon 2 (coding exon 2) of the CNDP1 gene. This alteration results from a C to A substitution at nucleotide position 82, causing the proline (P) at amino acid position 28 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	Benign	0.067
BayesDel_addAF	Benign	-0.31	T
BayesDel_noAF	Benign	-0.69
CADD	Benign	0.20
DANN	Benign	0.60
Eigen	Benign	-1.5
Eigen_PC	Benign	-1.5
FATHMM_MKL	Benign	0.046	N
M_CAP	Benign	0.0054	T
MetaRNN	Benign	0.056	T
MetaSVM	Benign	-0.96	T
PrimateAI	Benign	0.29	T
PROVEAN	Benign	-0.44	N
REVEL	Benign	0.0080
Sift	Benign	0.15	T
Sift4G	Benign	0.28	T
Vest4		0.21
MutPred		0.22		Gain of sheet (P = 0.0166);
MVP		0.048
MPC		0.18
ClinPred		0.050	T
GERP RS		-1.2
gMVP		0.27

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: rs1981041416; hg19: chr18-72223630;