18-74583526-T-A

Variant names:

• chr18-74583526-T-A
• rs11659237
• NM_032649.6:c.1310-35T>A

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_032649.6(CNDP1):​c.1310-35T>A variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000689 in 1,452,432 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. There are indicators that this mutation may affect the branch point..

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: CNDP1 NM_032649.6 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.40
• Publications: 11 publications found

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]

ZNF407-AS1 (HGNC:44331): (ZNF407 antisense RNA 1)

LOC124904324 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: This position, referring to a specific DNA site, is a probable branch point but is likely benign (scored 2 / 10, using the threshold of <=3). The score ranges from 0 to 10, with values ≤3 considered benign and >5 classified as pathogenic. Computational evidence support a benign effect (BayesDel_noAF=-0.82).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CNDP1	NM_032649.6	c.1310-35T>A		intron_variant	Intron 10 of 11	ENST00000358821.8	NP_116038.4
LOC124904324	XR_007066415.1	n.152A>T		non_coding_transcript_exon_variant	Exon 1 of 2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CNDP1	ENST00000358821.8	c.1310-35T>A		intron_variant	Intron 10 of 11	1	NM_032649.6	ENSP00000351682.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 6.88e-7 AC: 1 AN: 1452432 Hom.: 0 Cov.: 27 AF XY: 0.00000138 AC XY: 1 AN XY: 722570

⚠️ 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: 33320

American (AMR) AF: 0.00 AC: 0 AN: 44650

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25968

East Asian (EAS) AF: 0.00 AC: 0 AN: 39578

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 85966

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53336

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5744

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1103794

Other (OTH) AF: 0.00 AC: 0 AN: 60076

⚠️ 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.: 31

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.82
CADD	Benign	2.3
DANN	Benign	0.46
PhyloP100		1.4
BranchPoint Hunter		2.0

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

Other links and lift over

dbSNP: rs11659237; hg19: chr18-72250762;