chr6-32039745-G-T

Variant names:

• chr6-32039745-G-T
• rs373648076
• NM_000500.9:c.652-4G>T

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_000500.9(CYP21A2):​c.652-4G>T variant causes a splice region, intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000187 in 1,608,108 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 3/3 splice prediction tools predict no significant impact on normal splicing. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: 𝑓 0.0000066 (0 hom., cov: 31)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: CYP21A2 NM_000500.9 splice_region, intron
• Scores: Splicing: ADA: 0.00003158
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.227
• Publications: 0 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: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.65).

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.652-4G>T		splice_region intron	N/A	NP_000491.4
	CYP21A2	NM_001128590.4		c.562-4G>T		splice_region intron	N/A	NP_001122062.3	P08686-2
	CYP21A2	NM_001368143.2		c.247-4G>T		splice_region intron	N/A	NP_001355072.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYP21A2	ENST00000644719.2	MANE Select	c.652-4G>T		splice_region intron	N/A	ENSP00000496625.1	P08686-1
	CYP21A2	ENST00000960600.1		c.652-4G>T		splice_region intron	N/A	ENSP00000630659.1
	CYP21A2	ENST00000960597.1		c.652-4G>T		splice_region intron	N/A	ENSP00000630656.1

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 151984 Hom.: 0 Cov.: 31

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

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

GnomAD2 exomes AF: 0.00000416 AC: 1 AN: 240450 AF XY: 0.00

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00000923

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000137 AC: 2 AN: 1456124 Hom.: 0 Cov.: 61 AF XY: 0.00 AC XY: 0 AN XY: 723764

African (AFR) AF: 0.0000301 AC: 1 AN: 33276

American (AMR) AF: 0.00 AC: 0 AN: 44144

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26016

East Asian (EAS) AF: 0.00 AC: 0 AN: 39376

South Asian (SAS) AF: 0.00 AC: 0 AN: 84986

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 52976

Middle Eastern (MID) AF: 0.000174 AC: 1 AN: 5760

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1109450

Other (OTH) AF: 0.00 AC: 0 AN: 60140

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 151984 Hom.: 0 Cov.: 31 AF XY: 0.0000135 AC XY: 1 AN XY: 74210

⚠️ 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: 41374

American (AMR) AF: 0.0000655 AC: 1 AN: 15256

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5164

South Asian (SAS) AF: 0.00 AC: 0 AN: 4818

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10588

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 67998

Other (OTH) AF: 0.00 AC: 0 AN: 2090

⚠️ The allele balance in gnomAD version 4 Genomes is significantly skewed from the expected value of 0.5. (p-value = 0), which strongly suggests a high chance of mosaicism in these individuals.

Alfa AF: 0.0000165 Hom.: 0

Bravo AF: 0.00000378

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.65
CADD	Benign	2.8
DANN	Benign	0.55
PhyloP100		-0.23

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Benign	0.000032
dbscSNV1_RF	Benign	0.0020
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: rs373648076; hg19: chr6-32007522;