17-50195232-G-C

Variant names:

• chr17-50195232-G-C
• rs776229611
• NM_000088.4:c.1299C>G

Variant summary

Our verdict is Uncertain significance. The variant received 5 ACMG points: 5P and 0B. PM1 PM2 PP2

The NM_000088.4(COL1A1):​c.1299C>G​(p.Ser433Arg) variant causes a missense, splice region change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,460,144 control chromosomes in the GnomAD database, with no homozygous occurrence. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. S433S) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: COL1A1 NM_000088.4 missense, splice_region
• Scores: Splicing: ADA: 0.00001808
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.228
• Publications: 0 publications found

Genes affected

COL1A1 (HGNC:2197): (collagen type I alpha 1 chain) This gene encodes the pro-alpha1 chains of type I collagen whose triple helix comprises two alpha1 chains and one alpha2 chain. Type I is a fibril-forming collagen found in most connective tissues and is abundant in bone, cornea, dermis and tendon. Mutations in this gene are associated with osteogenesis imperfecta types I-IV, Ehlers-Danlos syndrome type VIIA, Ehlers-Danlos syndrome Classical type, Caffey Disease and idiopathic osteoporosis. Reciprocal translocations between chromosomes 17 and 22, where this gene and the gene for platelet-derived growth factor beta are located, are associated with a particular type of skin tumor called dermatofibrosarcoma protuberans, resulting from unregulated expression of the growth factor. Two transcripts, resulting from the use of alternate polyadenylation signals, have been identified for this gene. [provided by R. Dalgleish, Feb 2008]

COL1A1 Gene-Disease associations (from GenCC):

• Caffey disease

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), ClinGen, Orphanet, Ambry Genetics
• COL1A1-related Ehlers-Danlos syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• combined osteogenesis imperfecta and Ehlers-Danlos syndrome 1

  Inheritance: AD Classification: DEFINITIVE, MODERATE Submitted by: ClinGen, Ambry Genetics
• Ehlers-Danlos syndrome

  Inheritance: AD Classification: DEFINITIVE Submitted by: G2P
• Ehlers-Danlos syndrome, arthrochalasia type

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, G2P, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Orphanet
• osteogenesis imperfecta

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• osteogenesis imperfecta type 1

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• osteogenesis imperfecta type 2

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, Orphanet
• osteogenesis imperfecta type 3

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: ClinGen, Labcorp Genetics (formerly Invitae), Orphanet
• osteogenesis imperfecta type 4

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: ClinGen, G2P, Orphanet
• Ehlers-Danlos syndrome, classic type, 1

  Inheritance: AD Classification: MODERATE Submitted by: ClinGen
• Ehlers-Danlos syndrome, classic type

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Ehlers-Danlos/osteogenesis imperfecta syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• high bone mass osteogenesis imperfecta

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Uncertain_significance. The variant received 5 ACMG points.

• PM1: In a hotspot region, there are 7 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 2 uncertain in NM_000088.4
• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the COL1A1 gene, where missense mutations are typically associated with disease (based on misZ statistic). The gene has 368 curated pathogenic missense variants (we use a threshold of 10). The gene has 98 curated benign missense variants. Gene score misZ: 3.5319 (above the threshold of 3.09). Trascript score misZ: 5.7733 (above the threshold of 3.09). GenCC associations: The gene is linked to high bone mass osteogenesis imperfecta, Ehlers-Danlos syndrome, arthrochalasia type, combined osteogenesis imperfecta and Ehlers-Danlos syndrome 1, Caffey disease, osteogenesis imperfecta type 4, osteogenesis imperfecta type 3, Ehlers-Danlos syndrome, classic type, Ehlers-Danlos syndrome, osteogenesis imperfecta type 2, osteogenesis imperfecta type 1, Ehlers-Danlos syndrome, classic type, 1, Ehlers-Danlos/osteogenesis imperfecta syndrome.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000088.4. 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
	COL1A1	NM_000088.4	MANE Select	c.1299C>G	p.Ser433Arg	missense splice_region	Exon 19 of 51	NP_000079.2	P02452

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	COL1A1	ENST00000225964.10	TSL:1 MANE Select	c.1299C>G	p.Ser433Arg	missense splice_region	Exon 19 of 51	ENSP00000225964.6	P02452
	COL1A1	ENST00000861334.1		c.1299C>G	p.Ser433Arg	missense splice_region	Exon 19 of 51	ENSP00000531393.1
	COL1A1	ENST00000861339.1		c.1299C>G	p.Ser433Arg	missense splice_region	Exon 19 of 51	ENSP00000531398.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000205 AC: 3 AN: 1460144 Hom.: 0 Cov.: 34 AF XY: 0.00 AC XY: 0 AN XY: 726338

African (AFR) AF: 0.00 AC: 0 AN: 33436

American (AMR) AF: 0.00 AC: 0 AN: 44386

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26082

East Asian (EAS) AF: 0.00 AC: 0 AN: 39668

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86174

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53304

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5766

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111004

Other (OTH) AF: 0.00 AC: 0 AN: 60324

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.81
BayesDel_addAF	Uncertain	0.050	T
BayesDel_noAF	Benign	-0.17
CADD	Benign	11
DANN	Benign	0.89
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.0
FATHMM_MKL	Benign	0.62	D
M_CAP	Uncertain	0.20	D
MetaRNN	Uncertain	0.44	T
MetaSVM	Benign	-0.60	T
PhyloP100		-0.23
PrimateAI	Uncertain	0.61	T
PROVEAN	Benign	-1.5	N
REVEL	Uncertain	0.44
Sift	Benign	0.44	T
Sift4G	Benign	0.46	T
Vest4		0.40
MutPred		0.37		Loss of phosphorylation at S433 (P = 0.0034)
MVP		0.74
MPC		0.63
ClinPred		0.58	D
GERP RS		-7.1
gMVP		0.59
Mutation Taster		=62/38	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000018
dbscSNV1_RF	Benign	0.24
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: rs776229611; hg19: chr17-48272593;