20-187911-G-A

Position:

• chr20-187911-G-A

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2 PP3

The NM_001037732.3(DEFB128):​c.257C>T​(p.Pro86Leu) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

• Frequency: Genomes: not found (cov: 32)
• Consequence: DEFB128 NM_001037732.3 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 3.57

Genes affected

DEFB128 (HGNC:18106): (defensin beta 128) Defensins are cysteine-rich cationic polypeptides that are important in the immunologic response to invading microorganisms. The antimicrobial protein encoded by this gene is secreted and is a member of the beta defensin protein family. Beta defensin genes are found in several clusters throughout the genome, with this gene mapping to a cluster at 20p13. [provided by RefSeq, Nov 2014]

ACMG classification

Verdict is Uncertain_significance. Variant got 3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.747

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
DEFB128	NM_001037732.3	c.257C>T	p.Pro86Leu	missense_variant	2/2	ENST00000334391.5	NP_001032821.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
DEFB128	ENST00000334391.5	c.257C>T	p.Pro86Leu	missense_variant	2/2	1	NM_001037732.3	ENSP00000335382.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 32

GnomAD4 genome Cov.: 32

Asia WGS AF: 0.000577 AC: 2 AN: 3478

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

not specified Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Apr 09, 2024

The c.257C>T (p.P86L) alteration is located in exon 2 (coding exon 2) of the DEFB128 gene. This alteration results from a C to T substitution at nucleotide position 257, causing the proline (P) at amino acid position 86 to be replaced by a leucine (L). 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	0.81
BayesDel_addAF	Benign	-0.0035	T
BayesDel_noAF	Benign	-0.24
CADD	Benign	23
DANN	Uncertain	1.0
DEOGEN2	Benign	0.077	T
Eigen	Uncertain	0.35
Eigen_PC	Uncertain	0.23
FATHMM_MKL	Benign	0.75	D
LIST_S2	Benign	0.63	T
M_CAP	Benign	0.048	D
MetaRNN	Pathogenic	0.75	D
MetaSVM	Benign	-0.83	T
PrimateAI	Uncertain	0.63	T
PROVEAN	Pathogenic	-5.0	D
REVEL	Benign	0.23
Sift	Pathogenic	0.0	D
Sift4G	Pathogenic	0.0	D
Polyphen		1.0	D
Vest4		0.71
MutPred		0.55		Loss of loop (P = 0.0112);
MVP		0.29
MPC		0.036
ClinPred		1.0	D
GERP RS		4.3
Varity_R		0.48
gMVP		0.52

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.010		Details are displayed if max score is > 0.2

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Publications

LitVar

Other links and lift over

dbSNP: rs368724506; hg19: chr20-168552;