17-50188908-G-A

Position:

• chr17-50188908-G-A

Variant summary

Our verdict is Pathogenic. Variant got 15 ACMG points: 15P and 0B. PM1 PP2 PP3_Strong PP5_Very_Strong

The ENST00000225964.10(COL1A1):​c.3040C>T​(p.Arg1014Cys) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000551 in 1,451,640 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000055 (0 hom.)
• Consequence: COL1A1 ENST00000225964.10 missense
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:5 O:1
• Conservation: PhyloP100: 9.93

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]

ACMG classification

Verdict is Pathogenic. Variant got 15 ACMG points.

• PM1: In a hotspot region, there are 4 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 4 benign, 4 uncertain in ENST00000225964.10
• PP2: Missense variant in gene, where missense usually causes diseases (based on misZ statistic), COL1A1. . Gene score misZ 3.5319 (greater than the threshold 3.09). Trascript score misZ 5.7733 (greater than threshold 3.09). GenCC has associacion of gene with Caffey disease, Ehlers-Danlos/osteogenesis imperfecta syndrome, combined osteogenesis imperfecta and Ehlers-Danlos syndrome 1, Ehlers-Danlos syndrome, arthrochalasia type, osteogenesis imperfecta type 3, Ehlers-Danlos syndrome, classic type, 1, high bone mass osteogenesis imperfecta, osteogenesis imperfecta type 4, Ehlers-Danlos syndrome, classic type, osteogenesis imperfecta type 2, osteogenesis imperfecta type 1.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.941
• PP5: Variant 17-50188908-G-A is Pathogenic according to our data. Variant chr17-50188908-G-A is described in ClinVar as [Pathogenic]. Clinvar id is 17347.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars. Variant chr17-50188908-G-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
COL1A1	NM_000088.4	c.3040C>T	p.Arg1014Cys	missense_variant	41/51	ENST00000225964.10	NP_000079.2
COL1A1	XM_011524341.2	c.2842C>T	p.Arg948Cys	missense_variant	38/48		XP_011522643.1
COL1A1	XM_005257058.5	c.2770C>T	p.Arg924Cys	missense_variant	39/49		XP_005257115.2
COL1A1	XM_005257059.5	c.2122C>T	p.Arg708Cys	missense_variant	28/38		XP_005257116.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
COL1A1	ENST00000225964.10	c.3040C>T	p.Arg1014Cys	missense_variant	41/51	1	NM_000088.4	ENSP00000225964	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD3 exomes AF: 0.00000799 AC: 2 AN: 250334 Hom.: 0 AF XY: 0.00000738 AC XY: 1 AN XY: 135574

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.0000544

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000885

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000551 AC: 8 AN: 1451640 Hom.: 0 Cov.: 33 AF XY: 0.00000277 AC XY: 2 AN XY: 722746

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.00000635

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

Alfa AF: 0.0000457 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:5 Other:1

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

not provided Pathogenic:2

Pathogenic, criteria provided, single submitter	clinical testing	GeneDx	Apr 07, 2022	Skin biopsy from an affected adult with this variant demonstrated less densely packed collagen fibrils of variable shape and size surrounded by granular material, while analysis of collagen fibrils in cultured skin fibroblasts indicated increased disulfide crosslinking (Gensure et al., 2005); Not observed at significant frequency in large population cohorts (gnomAD); In silico analysis supports that this missense variant has a deleterious effect on protein structure/function; Located in the Gly-X-Y triple helical region of the pro-alpha1(I) chain encoded by the COL1A1 gene, where triplet glycine substitutions are the most common cause of osteogenesis imperfecta (OI). The effect of missense substitution at the X and Y positions are more difficult to predict; however, multiple variants that result in introduction of a Cys residue in pro-alpha1(I) have been reported to be pathogenic (Dalgleish, 1998); This variant is associated with the following publications: (PMID: 21249479, 22855962, 15864348, 18553566, 18704262, 17309652, 21567126, 24390061) -
Pathogenic, criteria provided, single submitter	clinical testing	ARUP Laboratories, Molecular Genetics and Genomics, ARUP Laboratories	May 21, 2020	The COL1A1 c.3040C>T; p.Arg1014Cys variant (rs72653170) is reported in the literature in numerous individuals and families affected with infantile cortical hyperostosis, also called Caffey disease (Cho 2008, Gensure 2005, Kitaoka 2014, Suphapeetiporn 2007). This variant has been observed to segregate with disease in multiple families, although it exhibits incomplete penetrance (Gensure 2005, Kitaoka 2014, Suphapeetiporn 2007). In one family, the variant was found in two affected identical twins but was absent from both parents, suggesting a de novo origin (Gensure 2005). This variant is found on only two chromosomes in the Genome Aggregation Database (2/250334 alleles), indicating it is not a common polymorphism. The arginine at codon 1014 is highly conserved, and computational analyses (SIFT, PolyPhen-2) predict that this variant is deleterious. Based on available information, this variant is considered to be pathogenic. References: Cho TJ et al. The c.3040C > T mutation in COL1A1 is recurrent in Korean patients with infantile cortical hyperostosis (Caffey disease). J Hum Genet. 2008;53(10):947. Gensure RC et al. A novel COL1A1 mutation in infantile cortical hyperostosis (Caffey disease) expands the spectrum of collagen-related disorders. J Clin Invest. 2005 May;115(5):1250-7. Kitaoka T et al. Two Japanese familial cases of Caffey disease with and without the common COL1A1 mutation and normal bone density, and review of the literature. Eur J Pediatr. 2014 Jun;173(6):799-804. Suphapeetiporn K et al. Expanding the phenotypic spectrum of Caffey disease. Clin Genet. 2007 Mar;71(3):280-4. -

Infantile cortical hyperostosis Pathogenic:1 Other:1

Pathogenic, no assertion criteria provided	literature only	OMIM	Jul 15, 2008	- -
not provided, no classification provided	literature only	GeneReviews	-	- -

Infantile cortical hyperostosis;C0023931:Osteogenesis imperfecta type I;C0029458:Postmenopausal osteoporosis;C0268358:Osteogenesis imperfecta, perinatal lethal;C0268362:Osteogenesis imperfecta type III;C0268363:Osteogenesis imperfecta with normal sclerae, dominant form;C4551623:Ehlers-Danlos syndrome, arthrochalasia type Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Fulgent Genetics, Fulgent Genetics

Oct 31, 2018

- -

Osteogenesis imperfecta type I Pathogenic:1

Pathogenic, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Oct 23, 2023

This sequence change replaces arginine, which is basic and polar, with cysteine, which is neutral and slightly polar, at codon 1014 of the COL1A1 protein (p.Arg1014Cys). This variant is present in population databases (rs72653170, gnomAD 0.006%). This missense change has been observed in individual(s) with Caffey disease (PMID: 15864348, 17309652, 18553566, 18704262, 21249479, 21567126, 24390061). It has also been observed to segregate with disease in related individuals. This variant is also known as p.Arg836Cys. ClinVar contains an entry for this variant (Variation ID: 17347). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt COL1A1 protein function with a positive predictive value of 95%. Experimental studies have shown that this missense change affects COL1A1 function (PMID: 15864348). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.83
BayesDel_addAF	Pathogenic	0.37	D
BayesDel_noAF	Pathogenic	0.47
CADD	Pathogenic	32
DANN	Uncertain	1.0
Eigen	Uncertain	0.68
Eigen_PC	Uncertain	0.60
FATHMM_MKL	Pathogenic	0.97	D
M_CAP	Pathogenic	0.57	D
MetaRNN	Pathogenic	0.94	D
MetaSVM	Pathogenic	1.0	D
MutationTaster	Benign	1.0	A
PrimateAI	Uncertain	0.74	T
PROVEAN	Pathogenic	-5.3	D
REVEL	Pathogenic	0.93
Sift	Uncertain	0.0010	D
Sift4G	Uncertain	0.022	D
Vest4		0.92
MutPred		0.70		Loss of methylation at R1014 (P = 0.0118);
MVP		0.99
MPC		0.77
ClinPred		0.98	D
GERP RS		4.0
gMVP		0.89

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		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

Other links and lift over

dbSNP: rs72653170; hg19: chr17-48266269; COSMIC: COSV104388046; COSMIC: COSV104388046;