17-35150090-G-A

Variant summary

Our verdict is Likely benign. Variant got -2 ACMG points: 2P and 4B. PP3_Moderate BS2

The NM_001267052.2(UNC45B):c.248G>A(p.Arg83Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.0000174 in 1,612,766 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 Uncertain significance (★).

• Frequency:
  • Genomes: 𝑓 0.000020 (0 hom., cov: 32)
  • Exomes 𝑓: 0.000017 (0 hom.)
• Consequence: UNC45B NM_001267052.2 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 9.80

Genes affected

UNC45B (HGNC:14304): (unc-45 myosin chaperone B) This gene encodes a co-chaperone required for folding and accumulation of type II myosins. The protein consists of three tetratricopeptide repeat motifs at the N-terminus that form a complex with heat shock protein 90, a central region of unknown function that is conserved in all Unc-45 proteins, and a C-terminal Unc-45/Cro1/She4 domain. The protein is expressed at high levels in striated muscle, where its muscle myosin chaperone activity is dependent on heat shock protein 90 acting as a co-chaperone. A missense mutation in this gene has been associated with cataract development. Alternative splicing results in multiple transcript variants. [provided by RefSeq, Apr 2015]

ACMG classification

Verdict is Likely_benign. Variant got -2 ACMG points.

• PP3: MetaRNN computational evidence supports a deleterious effect, 0.916
• BS2: High AC in GnomAdExome at 5 AD gene.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
UNC45B	NM_001267052.2	c.248G>A	p.Arg83Gln	missense_variant	4/20	ENST00000394570.7

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
UNC45B	ENST00000394570.7	c.248G>A	p.Arg83Gln	missense_variant	4/20	1	NM_001267052.2	P4
UNC45B	ENST00000591048.2	c.248G>A	p.Arg83Gln	missense_variant	3/17	1
UNC45B	ENST00000268876.9	c.248G>A	p.Arg83Gln	missense_variant	4/20	5		A1

Frequencies

GnomAD3 genomes AF: 0.0000197 AC: 3 AN: 152160 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.0000655

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: 0.0000200 AC: 5 AN: 249942 Hom.: 0 AF XY: 0.0000222 AC XY: 3 AN XY: 135060

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.00

Gnomad ASJ exome AF: 0.0000998

Gnomad EAS exome AF: 0.0000547

Gnomad SAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.0000265

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.0000171 AC: 25 AN: 1460606 Hom.: 0 Cov.: 30 AF XY: 0.0000110 AC XY: 8 AN XY: 726590

Gnomad4 AFR exome AF: 0.00

Gnomad4 AMR exome AF: 0.00

Gnomad4 ASJ exome AF: 0.0000383

Gnomad4 EAS exome AF: 0.00

Gnomad4 SAS exome AF: 0.00

Gnomad4 FIN exome AF: 0.00

Gnomad4 NFE exome AF: 0.0000198

Gnomad4 OTH exome AF: 0.0000166

GnomAD4 genome AF: 0.0000197 AC: 3 AN: 152160 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74322

Gnomad4 AFR AF: 0.00

Gnomad4 AMR AF: 0.0000655

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: 0.0000678 Hom.: 0

Bravo AF: 0.0000113

TwinsUK AF: 0.00 AC: 0

ALSPAC AF: 0.000259 AC: 1

ExAC AF: 0.0000247 AC: 3

EpiCase AF: 0.0000546

EpiControl AF: 0.0000593

ClinVar

Significance: Uncertain significance

Submissions summary: Uncertain:1

Revision: criteria provided, single submitter

Submissions by phenotype

Inborn genetic diseases Uncertain:1

Uncertain significance, criteria provided, single submitter

clinical testing

Ambry Genetics

Jun 14, 2023

The c.248G>A (p.R83Q) alteration is located in exon 4 (coding exon 3) of the UNC45B gene. This alteration results from a G to A substitution at nucleotide position 248, causing the arginine (R) at amino acid position 83 to be replaced by a glutamine (Q). 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	0.62
BayesDel_addAF	Pathogenic	0.25	D
BayesDel_noAF	Pathogenic	0.29
Cadd	Pathogenic	32
Dann	Pathogenic	1.0
DEOGEN2	Uncertain	0.57	D;.;.
Eigen	Pathogenic	0.91
Eigen_PC	Pathogenic	0.85
FATHMM_MKL	Pathogenic	0.99	D
LIST_S2	Pathogenic	0.99	D;D;D
M_CAP	Benign	0.064	D
MetaRNN	Pathogenic	0.92	D;D;D
MetaSVM	Uncertain	0.17	D
MutationAssessor	Pathogenic	3.3	M;M;M
MutationTaster	Benign	1.0	D;D;D;D;D
PrimateAI	Uncertain	0.69	T
PROVEAN	Uncertain	-3.4	D;D;.
REVEL	Uncertain	0.62
Sift	Uncertain	0.0030	D;D;.
Sift4G	Uncertain	0.012	D;D;D
Polyphen		1.0	D;D;D
Vest4		0.96
MutPred		0.76		Loss of methylation at R83 (P = 0.05);Loss of methylation at R83 (P = 0.05);Loss of methylation at R83 (P = 0.05);
MVP		0.91
MPC		0.53
ClinPred		0.96	D
GERP RS		4.5
Varity_R		0.67
gMVP		0.77

Splicing

Name	Calibrated prediction	Score	Prediction
SpliceAI score (max)		0.030		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: rs749498469; hg19: chr17-33477109;