NM_000500.9:c.188A>C

Variant names:

• chr6-32038610-A-C
• rs9378252
• NM_000500.9:c.188A>C

Variant summary

Our verdict is Uncertain significance. The variant received 3 ACMG points: 3P and 0B. PM2 PP2

The NM_000500.9(CYP21A2):​c.188A>C​(p.His63Pro) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Another variant affecting the same amino acid position, but resulting in a different missense (i.e. H63L) has been classified as Uncertain significance.

• Frequency: Genomes: not found (cov: 28)
• Consequence: CYP21A2 NM_000500.9 missense
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.135
• Publications: 26 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: Uncertain_significance. The variant received 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 52 curated pathogenic missense variants (we use a threshold of 10). The gene has 5 curated benign missense variants. Trascript score misZ: 1.8021 (below the threshold of 3.09). GenCC associations: The gene is linked to classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency, simple virilizing form, classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency, classic congenital adrenal hyperplasia due to 21-hydroxylase deficiency, salt wasting form.

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.188A>C	p.His63Pro	missense	Exon 1 of 10	NP_000491.4
	CYP21A2	NM_001128590.4		c.188A>C	p.His63Pro	missense	Exon 1 of 9	NP_001122062.3	P08686-2
	CYP21A2	NM_001368143.2		c.-237A>C		5_prime_UTR	Exon 1 of 10	NP_001355072.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYP21A2	ENST00000644719.2	MANE Select	c.188A>C	p.His63Pro	missense	Exon 1 of 10	ENSP00000496625.1	P08686-1
	CYP21A2	ENST00000960600.1		c.188A>C	p.His63Pro	missense	Exon 1 of 10	ENSP00000630659.1
	CYP21A2	ENST00000960597.1		c.188A>C	p.His63Pro	missense	Exon 1 of 10	ENSP00000630656.1

Frequencies

GnomAD3 genomes Cov.: 28

GnomAD4 exome Cov.: 36

GnomAD4 genome Cov.: 28

Alfa AF: 0.00 Hom.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.26
BayesDel_addAF	Uncertain	0.088	D
BayesDel_noAF	Benign	-0.11
CADD	Benign	20
DANN	Benign	0.81
DEOGEN2	Benign	0.067	T
Eigen	Benign	-0.79
Eigen_PC	Benign	-0.95
FATHMM_MKL	Benign	0.040	N
LIST_S2	Benign	0.79	T
M_CAP	Uncertain	0.28	D
MetaRNN	Uncertain	0.71	D
MetaSVM	Benign	-0.86	T
PhyloP100		-0.14
PrimateAI	Benign	0.33	T
PROVEAN	Uncertain	-2.5	N
REVEL	Uncertain	0.51
Sift	Benign	0.11	T
Sift4G	Uncertain	0.030	D
Polyphen		0.77	P
Vest4		0.30
MutPred		0.81		Loss of methylation at R61 (P = 0.0817)
MVP		0.98
MPC		3.5
ClinPred		0.29	T
GERP RS		-1.8
PromoterAI		-0.015	Neutral
gMVP		0.83
Mutation Taster		=38/62	disease causing

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: rs9378252; hg19: chr6-32006387;