9-114156007-C-T

Variant names:

• chr9-114156007-C-T
• rs941086447
• NM_032888.4:c.57C>T

Variant summary

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

The NM_032888.4(COL27A1):​c.57C>T​(p.Arg19Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. R19R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 31)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: COL27A1 NM_032888.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.0900
• 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 -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.57).
• BP7: Synonymous conserved (PhyloP=0.09 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL27A1	NM_032888.4	c.57C>T	p.Arg19Arg	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.57C>T	p.Arg19Arg	synonymous_variant	Exon 1 of 61	1	NM_032888.4	ENSP00000348385.3

Frequencies

GnomAD3 genomes Cov.: 31

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1145638 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 549246

African (AFR) AF: 0.00 AC: 0 AN: 24676

American (AMR) AF: 0.00 AC: 0 AN: 17282

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 15142

East Asian (EAS) AF: 0.00 AC: 0 AN: 30432

South Asian (SAS) AF: 0.00 AC: 0 AN: 26576

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 29292

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4546

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 951860

Other (OTH) AF: 0.00 AC: 0 AN: 45832

GnomAD4 genome Cov.: 31

Alfa AF: 0.00 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.57
CADD	Benign	11
DANN	Benign	0.97
PhyloP100		0.090
PromoterAI		-0.029	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.2

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: rs941086447; hg19: chr9-116918287;