chr17-41972016-G-A

Variant names:

• chr17-41972016-G-A
• rs1555643897
• NM_033133.5:c.801G>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_033133.5(CNP):​c.801G>A​(p.Glu267Glu) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,680 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.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CNP NM_033133.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.290
• Publications: 0 publications found

Genes affected

CNP (HGNC:2158): (2',3'-cyclic nucleotide 3' phosphodiesterase) Predicted to enable 2',3'-cyclic-nucleotide 3'-phosphodiesterase activity. Involved in substantia nigra development. Located in several cellular components, including extracellular space; microtubule; and plasma membrane. Implicated in hypomyelinating leukodystrophy 20; multiple sclerosis; and schizophrenia. Biomarker of alcoholic liver cirrhosis; multiple sclerosis; and restless legs syndrome. [provided by Alliance of Genome Resources, Apr 2022]

CNP Gene-Disease associations (from GenCC):

• leukodystrophy, hypomyelinating, 20

  Inheritance: Unknown, AR Classification: LIMITED Submitted by: Labcorp Genetics (formerly Invitae), Ambry Genetics

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.050188214).
• BP7: Synonymous conserved (PhyloP=-0.29 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_033133.5. 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
	CNP	NM_033133.5	MANE Select	c.801G>A	p.Glu267Glu	synonymous	Exon 3 of 4	NP_149124.3
	CNP	NM_001330216.2		c.741G>A	p.Glu247Glu	synonymous	Exon 3 of 4	NP_001317145.1	P09543-2

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CNP	ENST00000393892.8	TSL:1 MANE Select	c.801G>A	p.Glu267Glu	synonymous	Exon 3 of 4	ENSP00000377470.2	P09543-1
	CNP	ENST00000393888.1	TSL:1	c.741G>A	p.Glu247Glu	synonymous	Exon 3 of 4	ENSP00000377466.1	P09543-2
	CNP	ENST00000472031.1	TSL:2	c.128G>A	p.Ser43Asn	missense	Exon 2 of 3	ENSP00000467641.1	K7EQ27

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461680 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 727168

⚠️ 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: 33476

American (AMR) AF: 0.00 AC: 0 AN: 44704

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26120

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

South Asian (SAS) AF: 0.00 AC: 0 AN: 86256

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53406

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1111874

Other (OTH) AF: 0.00 AC: 0 AN: 60386

⚠️ 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

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.11
BayesDel_addAF	Benign	-0.36	T
BayesDel_noAF	Benign	-0.76
CADD	Benign	0.74
DANN	Benign	0.70
FATHMM_MKL	Benign	0.47	N
LIST_S2	Benign	0.27	T
M_CAP	Benign	0.040	D
MetaRNN	Benign	0.050	T
PhyloP100		-0.29
Vest4		0.056
MVP		0.33
GERP RS		-3.1
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.8

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: rs1555643897; hg19: chr17-40124034;