1-42754945-G-A

Variant names:

• chr1-42754945-G-A
• rs1553142371
• NM_022356.4:c.1269C>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4 BP6_Moderate BP7

The NM_022356.4(P3H1):​c.1269C>T​(p.Asn423Asn) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000137 in 1,461,884 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 (★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: P3H1 NM_022356.4 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: 3.03
• Publications: 0 publications found

Genes affected

P3H1 (HGNC:19316): (prolyl 3-hydroxylase 1) This gene encodes an enzyme that is a member of the collagen prolyl hydroxylase family. These enzymes are localized to the endoplasmic reticulum and their activity is required for proper collagen synthesis and assembly. Mutations in this gene are associated with osteogenesis imperfecta type VIII. Three alternatively spliced transcript variants encoding different isoforms have been described. Other variants may exist, but their biological validity has not been determined. [provided by RefSeq, Aug 2011]

P3H1 Gene-Disease associations (from GenCC):

• osteogenesis imperfecta type 8

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P
• osteogenesis imperfecta type 2

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (REVEL=0.267).
• BP6: Variant 1-42754945-G-A is Benign according to our data. Variant chr1-42754945-G-A is described in ClinVar as Likely_benign. ClinVar VariationId is 536821.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=3.03 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_022356.4. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	P3H1	NM_022356.4	MANE Select	c.1269C>T	p.Asn423Asn	synonymous	Exon 8 of 15	NP_071751.3
	P3H1	NM_001243246.2		c.1269C>T	p.Asn423Asn	synonymous	Exon 8 of 14	NP_001230175.1
	P3H1	NM_001146289.2		c.1269C>T	p.Asn423Asn	synonymous	Exon 8 of 15	NP_001139761.1

Ensembl Transcripts

Selected	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	P3H1	ENST00000296388.10	TSL:1 MANE Select	c.1269C>T	p.Asn423Asn	synonymous	Exon 8 of 15	ENSP00000296388.5
	P3H1	ENST00000397054.7	TSL:1	c.1269C>T	p.Asn423Asn	synonymous	Exon 8 of 15	ENSP00000380245.3
	P3H1	ENST00000236040.8	TSL:2	c.1269C>T	p.Asn423Asn	synonymous	Exon 8 of 14	ENSP00000236040.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461884 Hom.: 0 Cov.: 33 AF XY: 0.00 AC XY: 0 AN XY: 727242

⚠️ 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: 33478

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53418

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1112006

Other (OTH) AF: 0.00 AC: 0 AN: 60396

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0296732), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

Osteogenesis imperfecta type 8 Benign:1

Sep 11, 2017

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.37
CADD	Benign	8.8
DANN	Benign	0.88
PhyloP100		3.0
RBP_binding_hub_radar		1.0
RBP_regulation_power_radar		2.7
Mutation Taster		=99/1	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.020		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: rs1553142371; hg19: chr1-43220616;