NM_212550.5:c.34C>T

Variant names:

• chr19-45179330-C-T
• NM_212550.5:c.34C>T

Variant summary

Our verdict is Uncertain significance. The variant received 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_212550.5(BLOC1S3):​c.34C>T​(p.Arg12Trp) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.0000014 in 1,432,762 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. 12/21 in silico tools predict a benign outcome for this variant. Variant has been reported in ClinVar as Uncertain significance (★). Synonymous variant affecting the same amino acid position (i.e. R12R) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000014 (0 hom.)
• Consequence: BLOC1S3 NM_212550.5 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 1.18
• Publications: 0 publications found

Genes affected

BLOC1S3 (HGNC:20914): (biogenesis of lysosomal organelles complex 1 subunit 3) This gene encodes a protein that is a component of the BLOC1 multi-subunit protein complex. This complex is necessary for the biogenesis of specialized organelles of the endosomal-lysosomal system, including platelet dense granules and melanosomes. Mutations in this gene cause Hermansky-Pudlak syndrome 8, a disease characterized by lysosomal storage defects, bleeding due to platelet storage pool deficiency, and oculocutaneous albinism. [provided by RefSeq, Jul 2008]

MARK4 (HGNC:13538): (microtubule affinity regulating kinase 4) This gene encodes a member of the microtubule affinity-regulating kinase family. These protein kinases phosphorylate microtubule-associated proteins and regulate the transition between stable and dynamic microtubules. The encoded protein is associated with the centrosome throughout mitosis and may be involved in cell cycle control. Expression of this gene is a potential marker for cancer, and the encoded protein may also play a role in Alzheimer's disease. Pseudogenes of this gene are located on both the short and long arm of chromosome 3. Alternatively spliced transcript variants encoding multiple isoforms have been observed for this gene. [provided by RefSeq, Dec 2010]

MARK4 Gene-Disease associations (from GenCC):

• neurodevelopmental disorder

  Inheritance: AD Classification: LIMITED Submitted by: G2P

ACMG classification

Our verdict: Uncertain_significance. The variant received 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.23438218).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_212550.5. 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
	BLOC1S3	NM_212550.5	MANE Select	c.34C>T	p.Arg12Trp	missense	Exon 2 of 2	NP_997715.1	Q6QNY0

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BLOC1S3	ENST00000433642.3	TSL:2 MANE Select	c.34C>T	p.Arg12Trp	missense	Exon 2 of 2	ENSP00000393840.1	Q6QNY0
	BLOC1S3	ENST00000587722.1	TSL:6	c.34C>T	p.Arg12Trp	missense	Exon 1 of 1	ENSP00000468281.1	Q6QNY0
	BLOC1S3	ENST00000884249.1		c.34C>T	p.Arg12Trp	missense	Exon 2 of 3	ENSP00000554308.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 0.00000140 AC: 2 AN: 1432762 Hom.: 0 Cov.: 30 AF XY: 0.00000140 AC XY: 1 AN XY: 712752

⚠️ The allele balance in gnomAD version 4 Exomes is significantly skewed from the expected value of 0.5.

African (AFR) AF: 0.00 AC: 0 AN: 31720

American (AMR) AF: 0.00 AC: 0 AN: 43112

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 25638

East Asian (EAS) AF: 0.00 AC: 0 AN: 38296

South Asian (SAS) AF: 0.00 AC: 0 AN: 84112

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 38356

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5702

European-Non Finnish (NFE) AF: 0.00000181 AC: 2 AN: 1106238

Other (OTH) AF: 0.00 AC: 0 AN: 59588

⚠️ The allele balance in gnomAD4 Exomes is highly skewed from 0.5 (p-value = 0.0448430), which strongly suggests a high chance of mosaicism in these individuals.

GnomAD4 genome Cov.: 32

ClinVar

ClinVar submissions

Significance: Uncertain significance

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
-	1	-	not specified (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Benign	0.14
BayesDel_addAF	Uncertain	0.052	T
BayesDel_noAF	Benign	-0.16
CADD	Benign	19
DANN	Uncertain	0.99
DEOGEN2	Benign	0.36	T
Eigen	Benign	-0.35
Eigen_PC	Benign	-0.48
FATHMM_MKL	Benign	0.11	N
LIST_S2	Benign	0.71	T
M_CAP	Benign	0.040	D
MetaRNN	Benign	0.23	T
MetaSVM	Benign	-1.1	T
MutationAssessor	Benign	0.0	N
PhyloP100		1.2
PrimateAI	Pathogenic	0.83	D
PROVEAN	Uncertain	-3.3	D
REVEL	Benign	0.097
Sift	Uncertain	0.0040	D
Sift4G	Uncertain	0.024	D
Polyphen		0.99	D
Vest4		0.25
MutPred		0.21		Loss of solvent accessibility (P = 0.086)
MVP		0.37
MPC		1.8
ClinPred		0.70	D
GERP RS		2.9
PromoterAI		-0.00070	Neutral
Varity_R		0.21
gMVP		0.22
Mutation Taster		=98/2	polymorphism

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.040		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

hg19: chr19-45682588; COSMIC: COSV50065113; COSMIC: COSV50065113;