NM_001139.3:c.1859C>A

Variant names:

• chr17-8073215-G-T
• rs780420901
• NM_001139.3:c.1859C>A

Variant summary

Our verdict is Likely pathogenic. The variant received 8 ACMG points: 8P and 0B. PM2 PP2 PP3_Strong PP5

The NM_001139.3(ALOX12B):​c.1859C>A​(p.Pro620Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,888 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). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. P620L) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: ALOX12B NM_001139.3 missense
• Clinical Significance: Conflicting classifications of pathogenicity criteria provided, conflicting classifications P:2 U:1
• Conservation: PhyloP100: 9.08
• Publications: 1 publications found

Genes affected

ALOX12B (HGNC:430): (arachidonate 12-lipoxygenase, 12R type) This gene encodes an enzyme involved in the conversion of arachidonic acid to 12R-hydroxyeicosatetraenoic acid. Mutations in this gene are associated with nonbullous congenital ichthyosiform erythroderma. [provided by RefSeq, Sep 2015]

ALOX12B Gene-Disease associations (from GenCC):

• autosomal recessive congenital ichthyosis 2

  Inheritance: AR Classification: DEFINITIVE, STRONG Submitted by: Genomics England PanelApp, Labcorp Genetics (formerly Invitae), G2P
• congenital non-bullous ichthyosiform erythroderma

  Inheritance: AR Classification: STRONG, SUPPORTIVE Submitted by: Genomics England PanelApp, Orphanet
• lamellar ichthyosis

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet
• self-healing collodion baby

  Inheritance: AR Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_pathogenic. The variant received 8 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 70 curated pathogenic missense variants (we use a threshold of 10). The gene has 7 curated benign missense variants. Trascript score misZ: 1.7573 (below the threshold of 3.09). GenCC associations: The gene is linked to autosomal recessive congenital ichthyosis 2, congenital non-bullous ichthyosiform erythroderma, lamellar ichthyosis, self-healing collodion baby.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.962
• PP5: Variant 17-8073215-G-T is Pathogenic according to our data. Variant chr17-8073215-G-T is described in ClinVar as Conflicting_classifications_of_pathogenicity. ClinVar VariationId is 374101.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_001139.3. 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
	ALOX12B	NM_001139.3	MANE Select	c.1859C>A	p.Pro620Gln	missense	Exon 14 of 15	NP_001130.1	O75342

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	ALOX12B	ENST00000647874.1	MANE Select	c.1859C>A	p.Pro620Gln	missense	Exon 14 of 15	ENSP00000497784.1	O75342
	ALOX12B	ENST00000649809.1		c.923C>A	p.Pro308Gln	missense	Exon 7 of 8	ENSP00000496845.1	A0A3B3IRK2
	ALOX12B	ENST00000577351.5	TSL:5	n.583C>A		non_coding_transcript_exon	Exon 5 of 5

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.00000398 AC: 1 AN: 251462 AF XY: 0.00000736

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: 0.00000879

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461888 Hom.: 0 Cov.: 32 AF XY: 0.00000138 AC XY: 1 AN XY: 727246

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

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

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

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

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112010

Other (OTH) AF: 0.00 AC: 0 AN: 60396

GnomAD4 genome Cov.: 32

ExAC AF: 0.00000824 AC: 1

EpiCase AF: 0.00

EpiControl AF: 0.0000593

ClinVar

ClinVar submissions

Significance: Conflicting classifications of pathogenicity

Revision: criteria provided, conflicting classifications

Pathogenic	VUS	Benign	Condition
1	-	-	Autosomal recessive congenital ichthyosis 2 (1)
1	-	-	Ichthyosis (1)
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.96
BayesDel_addAF	Pathogenic	0.50	D
BayesDel_noAF	Pathogenic	0.48
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.92	D
Eigen	Pathogenic	0.81
Eigen_PC	Pathogenic	0.68
FATHMM_MKL	Uncertain	0.94	D
LIST_S2	Benign	0.77	T
M_CAP	Uncertain	0.28	D
MetaRNN	Pathogenic	0.96	D
MetaSVM	Pathogenic	1.1	D
MutationAssessor	Pathogenic	3.7	H
PhyloP100		9.1
PrimateAI	Uncertain	0.57	T
PROVEAN	Pathogenic	-7.6	D
REVEL	Pathogenic	0.90
Sift	Uncertain	0.0010	D
Sift4G	Pathogenic	0.0010	D
Polyphen		1.0	D
Vest4		0.85
MutPred		0.72		Loss of methylation at K623 (P = 0.1123)
MVP		0.95
MPC		1.4
ClinPred		1.0	D
GERP RS		5.1
Varity_R		0.95
gMVP		0.95
Mutation Taster		=53/47	disease causing (ClinVar)

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: rs780420901; hg19: chr17-7976533;