15-45587457-G-T

Position:

• chr15-45587457-G-T

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The ENST00000220531.9(BLOC1S6):​c.14G>T​(p.Gly5Val) 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 benign outcome for this variant. 15/19 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. G5E) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: BLOC1S6 ENST00000220531.9 missense
• Clinical Significance: Uncertain significance criteria provided, multiple submitters, no conflicts U:2
• Conservation: PhyloP100: -0.146

Genes affected

BLOC1S6 (HGNC:8549): (biogenesis of lysosomal organelles complex 1 subunit 6) The protein encoded by this gene may play a role in intracellular vesicle trafficking. It interacts with Syntaxin 13 which mediates intracellular membrane fusion. Mutations in this gene cause symptoms associated with Hermansky-Pudlak syndrome-9. Alternative splicing results in multiple transcript variants. A pseudogene related to this gene is located on the X chromosome. [provided by RefSeq, Aug 2015]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.04984671).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	Protein	UniProt
BLOC1S6	NM_012388.4	c.14G>T	p.Gly5Val	missense_variant	1/5	ENST00000220531.9	NP_036520.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Protein	Appris	UniProt
BLOC1S6	ENST00000220531.9	c.14G>T	p.Gly5Val	missense_variant	1/5	1	NM_012388.4	ENSP00000220531	P1

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1427362 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 706882

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: 0.00

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 33

ExAC AF: 0.00000836 AC: 1

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:2

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Hermansky-Pudlak syndrome 9 Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Labcorp Genetics (formerly Invitae), Labcorp

Aug 12, 2021

This sequence change replaces glycine with valine at codon 5 of the BLOC1S6 protein (p.Gly5Val). The glycine residue is moderately conserved and there is a moderate physicochemical difference between glycine and valine. The frequency data for this variant in the population databases is considered unreliable, as metrics indicate poor data quality at this position in the ExAC database. This variant has not been reported in the literature in individuals affected with BLOC1S6-related conditions. Algorithms developed to predict the effect of missense changes on protein structure and function output the following: SIFT: "Tolerated"; PolyPhen-2: "Benign"; Align-GVGD: "Class C0". The valine amino acid residue is found in multiple mammalian species, which suggests that this missense change does not adversely affect protein function. In summary, the available evidence is currently insufficient to determine the role of this variant in disease. Therefore, it has been classified as a Variant of Uncertain Significance. -

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Mar 29, 2024

The c.14G>T (p.G5V) alteration is located in exon 1 (coding exon 1) of the BLOC1S6 gene. This alteration results from a G to T substitution at nucleotide position 14, causing the glycine (G) at amino acid position 5 to be replaced by a valine (V). 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	Benign	0.069
BayesDel_addAF	Benign	-0.24	T
BayesDel_noAF	Benign	-0.59
CADD	Benign	12
DANN	Benign	0.94
DEOGEN2	Benign	0.40	T;T;T
Eigen	Benign	-1.1
Eigen_PC	Benign	-1.0
FATHMM_MKL	Benign	0.18	N
LIST_S2	Benign	0.69	T;T;T
M_CAP	Benign	0.0035	T
MetaRNN	Benign	0.050	T;T;T
MetaSVM	Benign	-1.0	T
MutationAssessor	Benign	0.69	N;.;.
MutationTaster	Benign	0.51	D;D;N;N;N
PrimateAI	Benign	0.43	T
PROVEAN	Benign	-2.0	N;D;N
REVEL	Benign	0.091
Sift	Benign	0.11	T;T;T
Sift4G	Uncertain	0.045	D;D;D
Polyphen		0.0	B;.;.
Vest4		0.073
MutPred		0.13		Gain of glycosylation at S7 (P = 0.0836);Gain of glycosylation at S7 (P = 0.0836);Gain of glycosylation at S7 (P = 0.0836);
MVP		0.11
MPC		0.51
ClinPred		0.049	T
GERP RS		-3.3
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.1
Varity_R		0.092

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

Other links and lift over

dbSNP: rs756977799; hg19: chr15-45879655;