20-54171649-C-G

Variant names:

• chr20-54171649-C-G
• NM_000782.5:c.471G>C
• CYP24A1 p.Arg157Arg

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Strong BP7

The NM_000782.5(CYP24A1):​c.471G>C​(p.Arg157Arg) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,680 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. R157R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: CYP24A1 NM_000782.5 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.504
• Publications: 0 publications found

Genes affected

CYP24A1 (HGNC:2602): (cytochrome P450 family 24 subfamily A member 1) 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 mitochondrial protein initiates the degradation of 1,25-dihydroxyvitamin D3, the physiologically active form of vitamin D3, by hydroxylation of the side chain. In regulating the level of vitamin D3, this enzyme plays a role in calcium homeostasis and the vitamin D endocrine system. Alternatively spliced transcript variants encoding different isoforms have been found for this gene. [provided by RefSeq, Jul 2008]

CYP24A1 Gene-Disease associations (from GenCC):

• hypercalcemia, infantile, 1

  Inheritance: AR Classification: STRONG, LIMITED Submitted by: Labcorp Genetics (formerly Invitae), G2P, Laboratory for Molecular Medicine
• autosomal recessive infantile hypercalcemia

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ENSG00000286587 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.5).
• BP7: Synonymous conserved (PhyloP=0.504 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000782.5. 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
	CYP24A1	NM_000782.5	MANE Select	c.471G>C	p.Arg157Arg	synonymous	Exon 3 of 12	NP_000773.2	Q07973-1
	CYP24A1	NM_001424340.1		c.471G>C	p.Arg157Arg	synonymous	Exon 3 of 12	NP_001411269.1	Q07973-1
	CYP24A1	NM_001424341.1		c.471G>C	p.Arg157Arg	synonymous	Exon 3 of 12	NP_001411270.1	Q07973-1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CYP24A1	ENST00000216862.8	TSL:1 MANE Select	c.471G>C	p.Arg157Arg	synonymous	Exon 3 of 12	ENSP00000216862.3	Q07973-1
	CYP24A1	ENST00000395955.7	TSL:1	c.471G>C	p.Arg157Arg	synonymous	Exon 3 of 11	ENSP00000379285.3	Q07973-2
	CYP24A1	ENST00000395954.3	TSL:1	c.45G>C	p.Arg15Arg	synonymous	Exon 1 of 10	ENSP00000379284.3	Q07973-3

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461680 Hom.: 0 Cov.: 33 AF XY: 0.00000138 AC XY: 1 AN XY: 727150

African (AFR) AF: 0.00 AC: 0 AN: 33472

American (AMR) AF: 0.00 AC: 0 AN: 44716

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

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86250

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53416

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5762

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 1111854

Other (OTH) AF: 0.0000166 AC: 1 AN: 60378

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.50
CADD	Benign	8.4
DANN	Benign	0.67
PhyloP100		0.50
PromoterAI		0.030	Neutral
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.7

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr20-52788188;