6-32040182-GT-GTT

Variant names:

• chr6-32040182-G-GT
• rs267606756
• NM_000500.9:c.923dupT

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_000500.9(CYP21A2):​c.923dupT​(p.Leu308PhefsTer6) variant causes a frameshift change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000131 in 152,214 control chromosomes in the GnomAD database, with no homozygous occurrence. Variant has been reported in ClinVar as Pathogenic (★★). Variant results in nonsense mediated mRNA decay.

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 33)
  • Exomes 𝑓: 0.000010 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: CYP21A2 NM_000500.9 frameshift
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:13 U:1
• Conservation: PhyloP100: -0.289
• Publications: 33 publications found

Genes affected

CYP21A2 (HGNC:2600): (cytochrome P450 family 21 subfamily A member 2) This gene encodes a member of the cytochrome P450 superfamily of enzymes. The cytochrome P450 proteins are monooxygenases which catalyze many reactions involved in drug metabolism and synthesis of cholesterol, steroids and other lipids. This protein localizes to the endoplasmic reticulum and hydroxylates steroids at the 21 position. Its activity is required for the synthesis of steroid hormones including cortisol and aldosterone. Mutations in this gene cause congenital adrenal hyperplasia. A related pseudogene is located near this gene; gene conversion events involving the functional gene and the pseudogene are thought to account for many cases of steroid 21-hydroxylase deficiency. Two transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

CYP21A2 Gene-Disease associations (from GenCC):

• classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), Myriad Women’s Health, Laboratory for Molecular Medicine
• classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency, salt wasting form

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency, simple virilizing form

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Loss of function variant, product undergoes nonsense mediated mRNA decay. LoF is a known mechanism of disease.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 6-32040182-G-GT is Pathogenic according to our data. Variant chr6-32040182-G-GT is described in ClinVar as Pathogenic. ClinVar VariationId is 65611.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000500.9. You can select a different transcript below to see updated ACMG assignments.

RefSeq Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYP21A2	NM_000500.9	MANE Select	c.923dupT	p.Leu308PhefsTer6	frameshift	Exon 7 of 10	NP_000491.4
	CYP21A2	NM_001128590.4		c.833dupT	p.Leu278PhefsTer6	frameshift	Exon 6 of 9	NP_001122062.3	P08686-2
	CYP21A2	NM_001368143.2		c.518dupT	p.Leu173PhefsTer6	frameshift	Exon 7 of 10	NP_001355072.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYP21A2	ENST00000644719.2	MANE Select	c.923dupT	p.Leu308PhefsTer6	frameshift	Exon 7 of 10	ENSP00000496625.1	P08686-1
	CYP21A2	ENST00000960600.1		c.959dupT	p.Leu320PhefsTer6	frameshift	Exon 7 of 10	ENSP00000630659.1
	CYP21A2	ENST00000960597.1		c.932dupT	p.Leu311PhefsTer6	frameshift	Exon 7 of 10	ENSP00000630656.1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152096 Hom.: 0 Cov.: 33

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

Gnomad ASJ AF: 0.00

Gnomad EAS AF: 0.000193

Gnomad SAS AF: 0.00

Gnomad FIN AF: 0.00

Gnomad MID AF: 0.00

Gnomad NFE AF: 0.0000147

Gnomad OTH AF: 0.00

GnomAD4 exome Data not reliable, filtered out with message: AS_VQSR AF: 0.0000103 AC: 15 AN: 1460516 Hom.: 0 Cov.: 38 AF XY: 0.00000688 AC XY: 5 AN XY: 726586

⚠️ 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: 33470

American (AMR) AF: 0.00 AC: 0 AN: 44714

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26132

East Asian (EAS) AF: 0.00 AC: 0 AN: 39698

South Asian (SAS) AF: 0.0000116 AC: 1 AN: 86248

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52306

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5760

European-Non Finnish (NFE) AF: 0.0000117 AC: 13 AN: 1111824

Other (OTH) AF: 0.00 AC: 0 AN: 60364

⚠️ 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: 0.0000131 AC: 2 AN: 152214 Hom.: 0 Cov.: 33 AF XY: 0.0000134 AC XY: 1 AN XY: 74424

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

African (AFR) AF: 0.00 AC: 0 AN: 41516

American (AMR) AF: 0.00 AC: 0 AN: 15304

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3470

East Asian (EAS) AF: 0.000193 AC: 1 AN: 5168

South Asian (SAS) AF: 0.00 AC: 0 AN: 4812

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10622

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 294

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68004

Other (OTH) AF: 0.00 AC: 0 AN: 2112

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0.0000000000983081), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.0000843 Hom.: 0

ClinVar

ClinVar submissions

Significance: Pathogenic

Revision: criteria provided, multiple submitters, no conflicts

Pathogenic	VUS	Benign	Condition
8	1	-	ADRENAL HYPERPLASIA, CONGENITAL, DUE TO 21-HYDROXYLASE DEFICIENCY (9)
5	-	-	not provided (5)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
PhyloP100		-0.29
Mutation Taster		=0/200	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: rs267606756; hg19: chr6-32007959; COSMIC: COSV64490649; COSMIC: COSV64490649;