9-114156001-G-A

Variant names:

• chr9-114156001-G-A
• rs2134975917
• NM_032888.4:c.51G>A

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 2P and 7B. PM2 BP4_Strong BP6_Moderate BP7

The NM_032888.4(COL27A1):​c.51G>A​(p.Ala17Ala) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000175 in 1,144,708 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. A17A) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0000017 (0 hom.)
• Consequence: COL27A1 NM_032888.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 1.81
• Publications: 0 publications found

Genes affected

COL27A1 (HGNC:22986): (collagen type XXVII alpha 1 chain) This gene encodes a member of the fibrillar collagen family, and plays a role during the calcification of cartilage and the transition of cartilage to bone. The encoded protein product is a preproprotein. It includes an N-terminal signal peptide, which is followed by an N-terminal propetide, mature peptide and a C-terminal propeptide. The N-terminal propeptide contains thrombospondin N-terminal-like and laminin G-like domains. The mature peptide is a major triple-helical region. The C-terminal propeptide, also known as COLFI domain, plays crucial roles in tissue growth and repair. Mutations in this gene cause Steel syndrome. Alternatively spliced transcript variants have been found, but the full-length nature of some variants has not been determined. [provided by RefSeq, Sep 2014]

COL27A1 Gene-Disease associations (from GenCC):

• Steel syndrome

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, G2P, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.52).
• BP6: Variant 9-114156001-G-A is Benign according to our data. Variant chr9-114156001-G-A is described in ClinVar as [Likely_benign]. Clinvar id is 2704609.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=1.81 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL27A1	NM_032888.4	c.51G>A	p.Ala17Ala	synonymous_variant	Exon 1 of 61	ENST00000356083.8	NP_116277.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL27A1	ENST00000356083.8	c.51G>A	p.Ala17Ala	synonymous_variant	Exon 1 of 61	1	NM_032888.4	ENSP00000348385.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome AF: 0.00000175 AC: 2 AN: 1144708 Hom.: 0 Cov.: 31 AF XY: 0.00000364 AC XY: 2 AN XY: 548774

African (AFR) AF: 0.00 AC: 0 AN: 24672

American (AMR) AF: 0.00 AC: 0 AN: 17276

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 15118

East Asian (EAS) AF: 0.00 AC: 0 AN: 30412

South Asian (SAS) AF: 0.00 AC: 0 AN: 26550

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 28858

Middle Eastern (MID) AF: 0.000220 AC: 1 AN: 4544

European-Non Finnish (NFE) AF: 0.00000105 AC: 1 AN: 951498

Other (OTH) AF: 0.00 AC: 0 AN: 45780

GnomAD4 genome Cov.: 31

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

not provided Benign:1

Dec 21, 2023

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.52
CADD	Benign	12
DANN	Benign	0.97
PhyloP100		1.8
PromoterAI		-0.014	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.9

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: rs2134975917; hg19: chr9-116918281;