Genetic Variant BLOC1S1:p.Ile136Thr (chr12-55719554-T-C) – ACMG Classification: Uncertain_significance (3 pts)

Variant summary

Our verdict is Uncertain significance. Variant got 3 ACMG points: 3P and 0B. PM2PP3

The NM_001487.4(BLOC1S1):c.407T>C(p.Ile136Thr) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000415 in 1,614,042 control chromosomes in the GnomAD database, including 1 homozygotes. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★).

Frequency

Genomes: 𝑓 0.000020 ( 0 hom., cov: 32)

Exomes 𝑓: 0.000044 ( 1 hom. )

Consequence

BLOC1S1
NM_001487.4 missense

Scores

Clinical Significance

Uncertain significance criteria provided, single submitter U:1

Conservation

PhyloP100: 7.70

Variant links:

Genes affected

BLOC1S1 (HGNC:4200): (biogenesis of lysosomal organelles complex 1 subunit 1) BLOC1S1 is a component of the ubiquitously expressed BLOC1 multisubunit protein complex. BLOC1 is required for normal biogenesis of specialized organelles of the endosomal-lysosomal system, such as melanosomes and platelet dense granules (Starcevic and Dell'Angelica, 2004 [PubMed 15102850]).[supplied by OMIM, Mar 2008]

BLOC1S1 links:

ENSG00000258311 (HGNC:):

ENSG00000258311 links:

Genome browser will be placed here

ACMG classification

Classification made for transcript

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, 0.816

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BLOC1S1	NM_001487.4 link	c.407T>C	p.Ile136Thr	missense_variant	Exon 4 of 4	ENST00000548925.6	NP_001478.2	P78537-1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BLOC1S1	ENST00000548925.6 link	c.407T>C	p.Ile136Thr	missense_variant	Exon 4 of 4	1	NM_001487.4	ENSP00000447537.1		P78537-1
ENSG00000258311	ENST00000550412.5 link	c.351+331T>C		intron_variant	Intron 3 of 3	2		ENSP00000447650.1		F8W036

Frequencies

GnomAD3 genomes

AF:

0.0000197

AC:

AN:

152158

Hom.:

Cov.:

show subpopulations

Gnomad AFR

AF:

0.0000241

Gnomad AMI

AF:

0.00

Gnomad AMR

AF:

0.00

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:

0.0000294

Gnomad OTH

AF:

0.00

GnomAD3 exomes

AF:

0.00000398

AC:

AN:

251476

Hom.:

AF XY:

0.00

AC XY:

AN XY:

135916

show subpopulations

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 SAS 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:

0.0000438

AC:

AN:

1461884

Hom.:

Cov.:

AF XY:

0.0000399

AC XY:

AN XY:

727244

show subpopulations

Gnomad4 AFR exome

AF:

0.00

Gnomad4 AMR exome

AF:

0.00

Gnomad4 ASJ exome

AF:

0.00

Gnomad4 EAS exome

AF:

0.00

Gnomad4 SAS exome

AF:

0.00

Gnomad4 FIN exome

AF:

0.00

Gnomad4 NFE exome

AF:

0.0000576

Gnomad4 OTH exome

AF:

0.00

GnomAD4 genome

AF:

0.0000197

AC:

AN:

152158

Hom.:

Cov.:

AF XY:

0.0000135

AC XY:

AN XY:

74320

show subpopulations

Gnomad4 AFR

AF:

0.0000241

Gnomad4 AMR

AF:

0.00

Gnomad4 ASJ

AF:

0.00

Gnomad4 EAS

AF:

0.00

Gnomad4 SAS

AF:

0.00

Gnomad4 FIN

AF:

0.00

Gnomad4 NFE

AF:

0.0000294

Gnomad4 OTH

AF:

0.00

Alfa

AF:

0.000130

Hom.:

Bravo

AF:

0.0000151

TwinsUK

AF:

0.000270

AC:

ALSPAC

AF:

0.000259

AC:

ExAC

AF:

0.00000824

AC:

EpiCase

AF:

0.000109

EpiControl

AF:

0.00

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

LINK: link

Submissions by phenotype

not specified

Uncertain:1

Oct 28, 2024

Ambry Genetics

Significance: Uncertain significance

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The c.407T>C (p.I136T) alteration is located in exon 4 (coding exon 4) of the BLOC1S1 gene. This alteration results from a T to C substitution at nucleotide position 407, causing the isoleucine (I) at amino acid position 136 to be replaced by a threonine (T). 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

0.98

BayesDel_addAF

Pathogenic

0.42

BayesDel_noAF

Pathogenic

0.37

CADD

Uncertain

DANN

Uncertain

1.0

DEOGEN2

Uncertain

0.50

D;T;T

Eigen

Uncertain

0.32

Eigen_PC

Uncertain

0.43

FATHMM_MKL

Pathogenic

0.99

LIST_S2

Uncertain

0.93

D;.;D

M_CAP

Benign

0.077

MetaRNN

Pathogenic

0.82

D;D;D

MetaSVM

Benign

-0.54

MutationAssessor

Uncertain

2.5

M;.;.

PrimateAI

Pathogenic

0.81

PROVEAN

Uncertain

-4.3

D;D;D

REVEL

Uncertain

0.57

Sift

Uncertain

0.0070

D;D;D

Sift4G

Uncertain

0.0040

D;D;D

Polyphen

0.21

B;.;.

Vest4

0.96

MVP

0.51

MPC

0.15

ClinPred

0.98

GERP RS

5.4

RBP_binding_hub_radar

0.0

RBP_regulation_power_radar

1.1

Varity_R

0.40

gMVP

0.95

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

LitVar

Below is the list of publications found by LitVar. It may be empty.

Variant summary

Frequency

Consequence

Scores

Clinical Significance

Conservation

ACMG classification

Transcripts

RefSeq

Ensembl

Frequencies

ClinVar

Submissions by phenotype

Computational scores

Splicing

Publications

LitVar

Other links and lift over