Genetic Variant CYLC1:p.Pro233Leu (chrX-83873406-C-T) – ACMG Classification: Likely_benign (-5 pts)

Variant summary

Our verdict is Likely benign. Variant got -5 ACMG points: 0P and 5B. BP4_StrongBS2_Supporting

The NM_021118.3(CYLC1):c.698C>T(p.Pro233Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000949 in 1,201,705 control chromosomes in the GnomAD database, with no homozygous occurrence. There are 45 hemizygotes in GnomAD. In-silico tool predicts a benign outcome for this variant. 14/20 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P233S) has been classified as Likely benign.

Frequency

Genomes: 𝑓 0.000027 ( 0 hom., 3 hem., cov: 22)

Exomes 𝑓: 0.00010 ( 0 hom. 42 hem. )

Consequence

CYLC1
NM_021118.3 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: -4.17

Variant links:

Genes affected

CYLC1 (HGNC:2582): (cylicin 1) This gene encodes a sperm head cytoskeletal protein. The encoded protein is associated with the calyx of spermatozoa and spermatids. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Nov 2012]

CYLC1 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

Verdict is Likely_benign. Variant got -5 ACMG points.

BP4

Computational evidence support a benign effect (MetaRNN=0.02347666).

BS2

High Hemizygotes in GnomAd4 at 3 geneVariant has number of hemizygotes lower than other variant known as pathogenic in the gene, so the strength is limited to Supporting.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
CYLC1	NM_021118.3 link	c.698C>T	p.Pro233Leu	missense_variant	Exon 4 of 5	ENST00000329312.5	NP_066941.1	P35663Q6PEK4
CYLC1	XM_005262086.5 link	c.695C>T	p.Pro232Leu	missense_variant	Exon 4 of 5		XP_005262143.1
CYLC1	NM_001271680.2 link	c.174+1836C>T		intron_variant	Intron 3 of 3		NP_001258609.1	A0A087WXC8

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
CYLC1	ENST00000329312.5 link	c.698C>T	p.Pro233Leu	missense_variant	Exon 4 of 5	1	NM_021118.3	ENSP00000331556.4		P35663
CYLC1	ENST00000621735.4 link	c.174+1836C>T		intron_variant	Intron 3 of 3	3		ENSP00000480907.1		A0A087WXC8

Frequencies

GnomAD3 genomes

AF:

0.0000271

AC:

AN:

110607

Hom.:

Cov.:

AF XY:

0.0000904

AC XY:

AN XY:

33181

show subpopulations

Gnomad AFR

AF:

0.00

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

Gnomad ASJ

AF:

0.00

Gnomad EAS

AF:

0.00

Gnomad SAS

AF:

0.00

Gnomad FIN

AF:

0.00

Gnomad MID

AF:

0.00

Gnomad NFE

AF:

0.0000571

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.0000686

AC:

AN:

174803

Hom.:

AF XY:

0.0000820

AC XY:

AN XY:

60969

show subpopulations

Gnomad AFR exome

AF:

0.00

Gnomad AMR exome

AF:

0.00

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:

0.000128

Gnomad OTH exome

AF:

0.000467

GnomAD4 exome

AF:

0.000102

AC:

111

AN:

1091098

Hom.:

Cov.:

AF XY:

0.000117

AC XY:

AN XY:

357742

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:

0.000152

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.000120

Gnomad4 OTH exome

AF:

0.0000437

GnomAD4 genome

AF:

0.0000271

AC:

AN:

110607

Hom.:

Cov.:

AF XY:

0.0000904

AC XY:

AN XY:

33181

show subpopulations

Gnomad4 AFR

AF:

0.00

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000571

Gnomad4 OTH

AF:

0.00

Bravo

AF:

0.0000604

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.000346

AC:

ExAC

AF:

0.000107

AC:

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Feb 08, 2025

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.698C>T (p.P233L) alteration is located in exon 4 (coding exon 4) of the CYLC1 gene. This alteration results from a C to T substitution at nucleotide position 698, causing the proline (P) at amino acid position 233 to be replaced by a leucine (L). 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

0.11

BayesDel_addAF

Benign

-0.74

BayesDel_noAF

Benign

-1.1

CADD

Benign

0.015

DANN

Benign

0.31

DEOGEN2

Benign

0.0028

FATHMM_MKL

Benign

0.0045

LIST_S2

Benign

0.43

M_CAP

Benign

0.0020

MetaRNN

Benign

0.023

MetaSVM

Benign

-1.0

MutationAssessor

Benign

0.0

PrimateAI

Benign

0.24

PROVEAN

Benign

-0.29

REVEL

Benign

0.010

Sift

Benign

0.40

Sift4G

Benign

0.26

Polyphen

0.0

Vest4

0.024

MutPred

0.21

Loss of methylation at K228 (P = 0.0492);

MVP

0.043

MPC

0.0020

ClinPred

0.033

GERP RS

-5.5

Varity_R

0.023

gMVP

0.012

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

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