rs12530380

Positions:

• chr6-32039810-T-A

Variant summary

Our verdict is Likely pathogenic. Variant got 9 ACMG points: 9P and 0B. PM1 PM2 PP3_Strong PP5

The NM_000500.9(CYP21A2):​c.713T>A​(p.Val238Glu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000248 in 1,613,928 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Conflicting classifications of pathogenicity (no stars).

• Frequency:
  • Genomes: 𝑓 0.000013 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CYP21A2 NM_000500.9 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:3 U:2
• Conservation: PhyloP100: 1.71

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]

ACMG classification

Verdict is Likely_pathogenic. Variant got 9 ACMG points.

• PM1: In a helix (size 22) in uniprot entity CP21A_HUMAN there are 11 pathogenic changes around while only 1 benign (92%) in NM_000500.9
• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.986
• PP5: Variant 6-32039810-T-A is Pathogenic according to our data. Variant chr6-32039810-T-A is described in ClinVar as [Conflicting_classifications_of_pathogenicity]. Clinvar id is 12173.We mark this variant Likely_pathogenic, oryginal submissions are: {Pathogenic=2, Likely_pathogenic=1, Uncertain_significance=2}. Variant chr6-32039810-T-A is described in Lovd as [Pathogenic].

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
CYP21A2	NM_000500.9	c.713T>A	p.Val238Glu	missense_variant	6/10	ENST00000644719.2
CYP21A2	NM_001128590.4	c.623T>A	p.Val208Glu	missense_variant	5/9
CYP21A2	NM_001368143.2	c.308T>A	p.Val103Glu	missense_variant	6/10
CYP21A2	NM_001368144.2	c.308T>A	p.Val103Glu	missense_variant	5/9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
CYP21A2	ENST00000644719.2	c.713T>A	p.Val238Glu	missense_variant	6/10		NM_000500.9	P1

Frequencies

GnomAD3 genomes AF: 0.0000131 AC: 2 AN: 152126 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.0000483

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: 0.00

Gnomad OTH AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1461684 Hom.: 0 Cov.: 64 AF XY: 0.00000138 AC XY: 1 AN XY: 727102

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.00

Gnomad4 EAS exome AF: 0.0000252

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 8.99e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome AF: 0.0000131 AC: 2 AN: 152244 Hom.: 0 Cov.: 31 AF XY: 0.0000134 AC XY: 1 AN XY: 74448

Gnomad4 AFR AF: 0.0000481

Gnomad4 AMR AF: 0.00

Gnomad4 ASJ AF: 0.00

Gnomad4 EAS AF: 0.00

Gnomad4 SAS AF: 0.00

Gnomad4 FIN AF: 0.00

Gnomad4 NFE AF: 0.00

Gnomad4 OTH AF: 0.00

ClinVar

Significance: Conflicting classifications of pathogenicity

Submissions summary: Pathogenic:3 Uncertain:2

Revision: criteria provided, conflicting classifications

Submissions by phenotype

not provided Pathogenic:2 Uncertain:1

Pathogenic, criteria provided, single submitter	clinical testing	Quest Diagnostics Nichols Institute San Juan Capistrano	Mar 28, 2021	- -
Pathogenic, criteria provided, single submitter	clinical testing	Clinical Genetics and Genomics, Karolinska University Hospital	May 23, 2017	- -
Uncertain significance, criteria provided, single submitter	clinical testing	Labcorp Genetics (formerly Invitae), Labcorp	Oct 31, 2022	This sequence change replaces valine, which is neutral and non-polar, with glutamic acid, which is acidic and polar, at codon 238 of the CYP21A2 protein (p.Val238Glu). The frequency data for this variant in the population databases (gnomAD) is considered unreliable due to the presence of homologous sequence, such as pseudogenes or paralogs, in the genome. The c.713T>A (p.Val238Glu) variant alone has been observed in an individual with classic salt-wasting congenital adrenal hyperplasia due to 21-hydroxylase deficiency (PMID: 26278268). It also frequently co-occurs with the c.710T>A (p.Ile237Asn) and c.719T>A (p.Met240Lys) variants in cis (on the same chromosome), which is known as the c.[710T>A;713T>A;719T>A] haplotype, E6 cluster, or CL6. This haplotype has been reported in the literature as homozygous or in combination with other CYP21A2 variants in individual(s) affected with classic salt-wasting, simple virilizing, and non-classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency (PMID: 12915679, 1644925, 23359698, 26804566). This variant is also known as p.V237E. ClinVar contains an entry for this variant (Variation ID: 12173). Advanced modeling of protein sequence and biophysical properties (such as structural, functional, and spatial information, amino acid conservation, physicochemical variation, residue mobility, and thermodynamic stability) performed at Invitae indicates that this missense variant is expected to disrupt CYP21A2 protein function. The c.713T>A (p.Val238Glu) variant alone affects CYP21A2 protein function, and the c.[710T>A;713T>A;719T>A] haplotype has been reported to abolish enzyme activity (PMID: 15623806). In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Congenital adrenal hyperplasia Pathogenic:1

Likely pathogenic, criteria provided, single submitter

clinical testing

Women's Health and Genetics/Laboratory Corporation of America, LabCorp

Dec 08, 2023

Variant summary: CYP21A2 c.713T>A (p.Val238Glu) results in a non-conservative amino acid change in the encoded protein sequence. Three of five in-silico tools predict a damaging effect of the variant on protein function. The frequency data for this variant in gnomAD is considered unreliable, as metrics indicate poor data quality at this position. p.V238E is found to be part of a recurrent cluster of 3 variants (I237N, V238E and M240K), which belongs to a group of common, pseudogene-derived mutations that are found in patients with classical CAH. This cluster of 3 variants is assumed to be transferred together from the CYP21A1P pseudogene to CYP21A2 in a continuous stretch of DNA (Robins_2005), and has been reported in the literature in multiple individuals affected with Congenital Adrenal Hyperplasia (e.g. Higashi_1991, Barbat_1995, Chang_2011, Kirac_2014, Essawi_2020, Wang_2021, Liu_2023, Faradz_2023 ). Nevertheless, p.V238E has also been reported in the literature to occur on its own in individuals affected with Congenital Adrenal Hyperplasia (e.g. Kirac_2014, Forouzanfar_2015, Fernandez_2020). These data indicate that the variant is likely to be associated with disease. Furthermore, experimental evidence evaluating an impact on protein function demonstrated that the p.V238E variant alone abolishes enzyme function and is thus a null mutation (Robins_2005). The following publications have been ascertained in the context of this evaluation (PMID: 7749410, 32616876, 21117955, 32614782, 32289882, 26278268, 1869518, 25227725, 16430727, 15623806, 2249999, 33864926, 37699373, 36726778). Four submitters have cited clinical-significance assessments for this variant to ClinVar after 2014 and classified the variant as pathogenic (n=2) and VUS (n=2). Based on the evidence outlined above, the variant was classified as likely pathogenic. -

Classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

3billion

May 22, 2022

The variant is observed at an extremely low frequency in the gnomAD v2.1.1 dataset (total allele frequency: <0.001%). Same nucleotide change resulting in same amino acid change has been previously reported to be associated with CYP21A2 related disorder (ClinVar ID: VCV000012173 / PMID: 26278268). Therefore, this variant is classified as pathogenic according to the recommendation of ACMG/AMP guideline. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.22	D
BayesDel_noAF	Uncertain	0.080
CADD	Uncertain	24
DANN	Uncertain	0.98
Eigen	Benign	-0.16
Eigen_PC	Benign	-0.30
FATHMM_MKL	Benign	0.17	N
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.99	D;D;D;D
MetaSVM	Benign	-0.60	T
MutationTaster	Benign	4.1e-8	A;A
PrimateAI	Benign	0.47	T
PROVEAN	Uncertain	-3.2	D;.;D;.
REVEL	Uncertain	0.44
Sift	Benign	0.043	D;.;D;.
Sift4G	Benign	0.097	T;.;T;.
Polyphen		0.83	P;P;.;P
Vest4		0.90
MutPred		0.91		Gain of disorder (P = 0.0013);Gain of disorder (P = 0.0013);.;Gain of disorder (P = 0.0013);
MVP		1.0
MPC		1.5
ClinPred		0.96	D
GERP RS		4.1
gMVP		0.86

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

Publications

LitVar

Other links and lift over

dbSNP: rs12530380; hg19: chr6-32007587;