chr16-30988111-CCT-C

Variant names:

• chr16-30988111-CCT-C
• rs397514442
• NM_025193.4:c.1039_1040delCT

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PVS1_Moderate PM2 PP5_Moderate

The NM_025193.4(HSD3B7):​c.1039_1040delCT​(p.Leu347ValfsTer6) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000688 in 1,453,852 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 34)
  • Exomes 𝑓: 6.9e-7 (0 hom.)
• Consequence: HSD3B7 NM_025193.4 frameshift
• Clinical Significance: Pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 1.94
• Publications: 3 publications found

Genes affected

HSD3B7 (HGNC:18324): (hydroxy-delta-5-steroid dehydrogenase, 3 beta- and steroid delta-isomerase 7) This gene encodes an enzyme which is involved in the initial stages of the synthesis of bile acids from cholesterol and a member of the short-chain dehydrogenase/reductase superfamily. The encoded protein is a membrane-associated endoplasmic reticulum protein which is active against 7-alpha hydrosylated sterol substrates. Mutations in this gene are associated with a congenital bile acid synthesis defect which leads to neonatal cholestasis, a form of progressive liver disease. Multiple transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Dec 2008]

HSD3B7 Gene-Disease associations (from GenCC):

• congenital bile acid synthesis defect 1

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, G2P, Labcorp Genetics (formerly Invitae)

ENSG00000279196 (HGNC:):

ACMG classification

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

• PVS1: Loss of function variant, product does not undergo nonsense mediated mRNA decay. Variant is located in the 3'-most exon, not predicted to undergo nonsense mediated mRNA decay. Fraction of 0.064 CDS is truncated, and there are 1 pathogenic variants in the truncated region.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 16-30988111-CCT-C is Pathogenic according to our data. Variant chr16-30988111-CCT-C is described in ClinVar as [Pathogenic]. Clinvar id is 2881.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
HSD3B7	NM_025193.4	c.1039_1040delCT	p.Leu347ValfsTer6	frameshift_variant	Exon 7 of 7	ENST00000297679.10	NP_079469.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
HSD3B7	ENST00000297679.10	c.1039_1040delCT	p.Leu347ValfsTer6	frameshift_variant	Exon 7 of 7	1	NM_025193.4	ENSP00000297679.5
ENSG00000279196	ENST00000624286.1	n.158_159delAG		non_coding_transcript_exon_variant	Exon 1 of 1	6
HSD3B7	ENST00000262520.10	c.*285_*286delCT		3_prime_UTR_variant	Exon 6 of 6	2		ENSP00000262520.6

Frequencies

GnomAD3 genomes Cov.: 34

GnomAD4 exome AF: 6.88e-7 AC: 1 AN: 1453852 Hom.: 0 AF XY: 0.00 AC XY: 0 AN XY: 723040

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

African (AFR) AF: 0.0000299 AC: 1 AN: 33416

American (AMR) AF: 0.00 AC: 0 AN: 44662

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26114

East Asian (EAS) AF: 0.00 AC: 0 AN: 39638

South Asian (SAS) AF: 0.00 AC: 0 AN: 86194

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 47552

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1110254

Other (OTH) AF: 0.00 AC: 0 AN: 60264

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.000000), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 34

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, single submitter

Submissions by phenotype

Congenital bile acid synthesis defect 1 Pathogenic:2

Apr 04, 2024

Genomic Medicine Center of Excellence, King Faisal Specialist Hospital and Research Centre

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Apr 01, 2003

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
PhyloP100		1.9
Mutation Taster		=13/187	disease causing (ClinVar)

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: rs397514442; hg19: chr16-30999432;