chr17-50188799-CAGAG-C

Variant names:

• chr17-50188799-CAGAG-C
• rs138425306
• NM_000088.4:c.3046-8_3046-5delCTCT

Variant summary

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

The NM_000088.4(COL1A1):​c.3046-8_3046-5delCTCT variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000288 in 1,530,080 control chromosomes in the GnomAD database, with no homozygous occurrence. There is a variant allele frequency bias in the population database for this variant (GnomAdExome4), which may indicate mosaicism or somatic mutations in the reference population data. 1/1 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.0000067 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000031 (0 hom.)
• Consequence: COL1A1 NM_000088.4 splice_region, intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 1.14
• Publications: 6 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: Ambry Genetics, Orphanet, Labcorp Genetics (formerly Invitae), G2P, ClinGen
• combined osteogenesis imperfecta and Ehlers-Danlos syndrome 1

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

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

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, PanelApp Australia, G2P, Genomics England PanelApp, Labcorp Genetics (formerly Invitae), ClinGen
• osteogenesis imperfecta type 1

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

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, ClinGen
• 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: G2P, Orphanet, ClinGen
• 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 0 ACMG points.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
COL1A1	NM_000088.4	c.3046-8_3046-5delCTCT		splice_region_variant, intron_variant	Intron 41 of 50	ENST00000225964.10	NP_000079.2
COL1A1	XM_011524341.2	c.2848-8_2848-5delCTCT		splice_region_variant, intron_variant	Intron 38 of 47		XP_011522643.1
COL1A1	XM_005257058.5	c.2776-8_2776-5delCTCT		splice_region_variant, intron_variant	Intron 39 of 48		XP_005257115.2
COL1A1	XM_005257059.5	c.2128-8_2128-5delCTCT		splice_region_variant, intron_variant	Intron 28 of 37		XP_005257116.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
COL1A1	ENST00000225964.10	c.3046-8_3046-5delCTCT		splice_region_variant, intron_variant	Intron 41 of 50	1	NM_000088.4	ENSP00000225964.6
COL1A1	ENST00000486572.1	n.-249_-246delCTCT		upstream_gene_variant		3
COL1A1	ENST00000511732.1	n.-19_-16delCTCT		upstream_gene_variant		2

Frequencies

GnomAD3 genomes AF: 0.00000667 AC: 1 AN: 149978 Hom.: 0 Cov.: 32

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: 0.0000149

Gnomad OTH AF: 0.00

GnomAD2 exomes AF: 0.0000427 AC: 3 AN: 70316 AF XY: 0.0000282

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.000620

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000556

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000312 AC: 43 AN: 1380102 Hom.: 0 AF XY: 0.0000364 AC XY: 25 AN XY: 687638

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 31790

American (AMR) AF: 0.00 AC: 0 AN: 43030

Ashkenazi Jewish (ASJ) AF: 0.0000407 AC: 1 AN: 24570

East Asian (EAS) AF: 0.00 AC: 0 AN: 36944

South Asian (SAS) AF: 0.00 AC: 0 AN: 84284

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 50210

Middle Eastern (MID) AF: 0.000182 AC: 1 AN: 5502

European-Non Finnish (NFE) AF: 0.0000392 AC: 41 AN: 1046982

Other (OTH) AF: 0.00 AC: 0 AN: 56790

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome AF: 0.00000667 AC: 1 AN: 149978 Hom.: 0 Cov.: 32 AF XY: 0.0000137 AC XY: 1 AN XY: 73192

African (AFR) AF: 0.00 AC: 0 AN: 41054

American (AMR) AF: 0.00 AC: 0 AN: 15044

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3448

East Asian (EAS) AF: 0.00 AC: 0 AN: 5162

South Asian (SAS) AF: 0.00 AC: 0 AN: 4790

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 9928

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 312

European-Non Finnish (NFE) AF: 0.0000149 AC: 1 AN: 67268

Other (OTH) AF: 0.00 AC: 0 AN: 2060

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
PhyloP100		1.1
Mutation Taster		=71/29	polymorphism

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: rs138425306; hg19: chr17-48266160;