8-38150754-C-T

Variant names:

• chr8-38150754-C-T
• rs765968701
• NM_000349.3:c.64+1G>A

Variant summary

Our verdict is Pathogenic. The variant received 14 ACMG points: 14P and 0B. PVS1_Strong PM2 PP5_Very_Strong

The NM_000349.3(STAR):​c.64+1G>A variant causes a splice donor, intron change. The variant allele was found at a frequency of 0.00000206 in 1,454,778 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 30)
  • Exomes 𝑓: 0.0000021 (0 hom.)
• Consequence: STAR NM_000349.3 splice_donor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic/Likely pathogenic criteria provided, multiple submitters, no conflicts P:2
• Conservation: PhyloP100: 6.92
• Publications: 0 publications found

Genes affected

STAR (HGNC:11359): (steroidogenic acute regulatory protein) The protein encoded by this gene plays a key role in the acute regulation of steroid hormone synthesis by enhancing the conversion of cholesterol into pregnenolone. This protein permits the cleavage of cholesterol into pregnenolone by mediating the transport of cholesterol from the outer mitochondrial membrane to the inner mitochondrial membrane. Mutations in this gene are a cause of congenital lipoid adrenal hyperplasia (CLAH), also called lipoid CAH. A pseudogene of this gene is located on chromosome 13. [provided by RefSeq, Jul 2008]

STAR Gene-Disease associations (from GenCC):

• congenital lipoid adrenal hyperplasia due to STAR deficency

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Myriad Women’s Health

ENSG00000253356 (HGNC:):

ACMG classification

Our verdict: Pathogenic. The variant received 14 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, product NOT destroyed by NMD, known LOF gene, truncates exone, which is 0.23076923 fraction of the gene.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 8-38150754-C-T is Pathogenic according to our data. Variant chr8-38150754-C-T is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 1070762.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
STAR	NM_000349.3	c.64+1G>A		splice_donor_variant, intron_variant	Intron 1 of 6	ENST00000276449.9	NP_000340.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
STAR	ENST00000276449.9	c.64+1G>A		splice_donor_variant, intron_variant	Intron 1 of 6	1	NM_000349.3	ENSP00000276449.3
STAR	ENST00000520114.1	n.238+1G>A		splice_donor_variant, intron_variant	Intron 1 of 3	2
ENSG00000253356	ENST00000520598.1	n.99+1915C>T		intron_variant	Intron 1 of 1	4

Frequencies

GnomAD3 genomes Cov.: 30

GnomAD4 exome AF: 0.00000206 AC: 3 AN: 1454778 Hom.: 0 Cov.: 31 AF XY: 0.00000138 AC XY: 1 AN XY: 724128

African (AFR) AF: 0.00 AC: 0 AN: 33478

American (AMR) AF: 0.0000224 AC: 1 AN: 44722

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39696

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

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 46406

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

European-Non Finnish (NFE) AF: 0.00000180 AC: 2 AN: 1111964

Other (OTH) AF: 0.00 AC: 0 AN: 60350

GnomAD4 genome Cov.: 30

ClinVar

Significance: Pathogenic/Likely pathogenic

Submissions summary: Pathogenic:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Congenital lipoid adrenal hyperplasia due to STAR deficency Pathogenic:1

Jun 03, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

not provided Pathogenic:1

Jan 14, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

This sequence change affects a donor splice site in intron 1 of the STAR gene. It is expected to disrupt RNA splicing. Variants that disrupt the donor or acceptor splice site typically lead to a loss of protein function (PMID: 16199547), and loss-of-function variants in STAR are known to be pathogenic (PMID: 8948562). This variant is not present in population databases (gnomAD no frequency). Disruption of this splice site has been observed in individual(s) with lipoid adrenal hyperplasia (PMID: 14764819, 25383892). ClinVar contains an entry for this variant (Variation ID: 1070762). Algorithms developed to predict the effect of variants on protein structure and function are not available or were not evaluated for this variant. Studies have shown that disruption of this splice site alters mRNA splicing and is expected to lead to the loss of protein expression (PMID: 14764819). For these reasons, this variant has been classified as Pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.60	D
BayesDel_noAF	Pathogenic	0.43
CADD	Pathogenic	34
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.96
FATHMM_MKL	Uncertain	0.97	D
PhyloP100		6.9
GERP RS		5.2
PromoterAI		-0.39	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7
Mutation Taster		=0/100	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_DL_spliceai		0.99		Position offset: 1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs765968701; hg19: chr8-38008272;