19-40991424-T-C

Variant summary

Our verdict is Likely pathogenic. The variant received 6 ACMG points: 6P and 0B. PM2PP3_Strong

The NM_000767.5(CYP2B6):​c.119T>C​(p.Leu40Ser) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000205 in 1,461,876 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 Uncertain significance (★).

Frequency

Genomes: not found (cov: 31)
Exomes 𝑓: 0.0000021 ( 0 hom. )

Consequence

CYP2B6
NM_000767.5 missense

Scores

6
6
7

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 2.04

Publications

1 publications found
Variant links:
Genes affected
CYP2B6 (HGNC:2615): (cytochrome P450 family 2 subfamily B member 6) This gene, CYP2B6, 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 its expression is induced by phenobarbital. The enzyme is known to metabolize some xenobiotics, such as the anti-cancer drugs cyclophosphamide and ifosphamide. Transcript variants for this gene have been described; however, it has not been resolved whether these transcripts are in fact produced by this gene or by a closely related pseudogene, CYP2B7. Both the gene and the pseudogene are located in the middle of a CYP2A pseudogene found in a large cluster of cytochrome P450 genes from the CYP2A, CYP2B and CYP2F subfamilies on chromosome 19q. [provided by RefSeq, Jul 2008]

Genome browser will be placed here

ACMG classification

Classification was made for transcript

Our verdict: Likely_pathogenic. The variant received 6 ACMG points.

PM2
Very rare variant in population databases, with high coverage;
PP3
MetaRNN computational evidence supports a deleterious effect, 0.942

Transcripts

RefSeq

Gene Transcript HGVSc HGVSp Effect Exon rank MANE Protein UniProt
CYP2B6NM_000767.5 linkc.119T>C p.Leu40Ser missense_variant Exon 1 of 9 ENST00000324071.10 NP_000758.1 P20813-1

Ensembl

Gene Transcript HGVSc HGVSp Effect Exon rank TSL MANE Protein Appris UniProt
CYP2B6ENST00000324071.10 linkc.119T>C p.Leu40Ser missense_variant Exon 1 of 9 1 NM_000767.5 ENSP00000324648.2 P20813-1
CYP2B6ENST00000598834.2 linkn.20T>C non_coding_transcript_exon_variant Exon 1 of 10 5 ENSP00000496294.1 A0A2R8YFA4

Frequencies

GnomAD3 genomes
Cov.:
31
GnomAD2 exomes
AF:
0.00000796
AC:
2
AN:
251410
AF XY:
0.00000736
show subpopulations
Gnomad AFR exome
AF:
0.00
Gnomad AMR exome
AF:
0.0000578
Gnomad ASJ exome
AF:
0.00
Gnomad EAS exome
AF:
0.00
Gnomad FIN exome
AF:
0.00
Gnomad NFE exome
AF:
0.00
Gnomad OTH exome
AF:
0.00
GnomAD4 exome
AF:
0.00000205
AC:
3
AN:
1461876
Hom.:
0
Cov.:
32
AF XY:
0.00000138
AC XY:
1
AN XY:
727238
show subpopulations
African (AFR)
AF:
0.00
AC:
0
AN:
33474
American (AMR)
AF:
0.0000671
AC:
3
AN:
44724
Ashkenazi Jewish (ASJ)
AF:
0.00
AC:
0
AN:
26136
East Asian (EAS)
AF:
0.00
AC:
0
AN:
39698
South Asian (SAS)
AF:
0.00
AC:
0
AN:
86254
European-Finnish (FIN)
AF:
0.00
AC:
0
AN:
53420
Middle Eastern (MID)
AF:
0.00
AC:
0
AN:
5762
European-Non Finnish (NFE)
AF:
0.00
AC:
0
AN:
1112012
Other (OTH)
AF:
0.00
AC:
0
AN:
60396
Allele Balance Distribution
Red line indicates average allele balance
Average allele balance: 0.508
Heterozygous variant carriers
0
1
1
2
2
3
0.00
0.20
0.40
0.60
0.80
0.95
Allele balance

Age Distribution

Exome Het
Variant carriers
0
2
4
6
8
10
<30
30-35
35-40
40-45
45-50
50-55
55-60
60-65
65-70
70-75
75-80
>80
Age
GnomAD4 genome
Cov.:
31
Alfa
AF:
0.00
Hom.:
0
Bravo
AF:
0.00000378

ClinVar

Significance: Uncertain significance
Submissions summary: Uncertain:1
Revision: criteria provided, single submitter
LINK: link

Submissions by phenotype

not specified Uncertain:1
May 26, 2025
Ambry Genetics
Significance:Uncertain significance
Review Status:criteria provided, single submitter
Collection Method:clinical testing

The c.119T>C (p.L40S) alteration is located in exon 1 (coding exon 1) of the CYP2B6 gene. This alteration results from a T to C substitution at nucleotide position 119, causing the leucine (L) at amino acid position 40 to be replaced by a serine (S). Based on insufficient or conflicting evidence, the clinical significance of this alteration remains unclear. -

Computational scores

Source: dbNSFP v4.3

Name
Calibrated prediction
Score
Prediction
AlphaMissense
Pathogenic
0.63
BayesDel_addAF
Benign
-0.030
T
BayesDel_noAF
Benign
-0.10
CADD
Uncertain
24
DANN
Uncertain
1.0
DEOGEN2
Benign
0.033
T;T
Eigen
Uncertain
0.38
Eigen_PC
Benign
0.19
FATHMM_MKL
Benign
0.47
N
LIST_S2
Uncertain
0.87
.;D
M_CAP
Benign
0.0066
T
MetaRNN
Pathogenic
0.94
D;D
MetaSVM
Uncertain
0.14
D
MutationAssessor
Pathogenic
4.1
H;H
PhyloP100
2.0
PrimateAI
Uncertain
0.52
T
PROVEAN
Pathogenic
-4.8
.;D
REVEL
Uncertain
0.64
Sift
Pathogenic
0.0
.;D
Sift4G
Pathogenic
0.0010
.;D
Polyphen
1.0
D;D
Vest4
0.62
MutPred
0.83
Gain of disorder (P = 0.0121);Gain of disorder (P = 0.0121);
MVP
0.87
MPC
0.45
ClinPred
1.0
D
GERP RS
3.1
PromoterAI
0.068
Neutral
Varity_R
0.87
gMVP
0.54
Mutation Taster
=78/22
polymorphism

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

Other links and lift over

dbSNP: rs1317585439; hg19: chr19-41497329; API