11-61959949-A-G

Variant summary

Our verdict is Uncertain significance. Variant got 0 ACMG points: 2P and 2B. PM2 BP4_Moderate

The NM_004183.4(BEST1):c.1006A>G(p.Met336Val) variant causes a missense change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.000000685 in 1,460,920 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 (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. M336R) has been classified as Uncertain significance.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: BEST1 NM_004183.4 missense
• Clinical Significance: Uncertain significance criteria provided, single submitter U:1
• Conservation: PhyloP100: 0.796

Genes affected

BEST1 (HGNC:12703): (bestrophin 1) This gene encodes a member of the bestrophin gene family. This small gene family is characterized by proteins with a highly conserved N-terminus with four to six transmembrane domains. Bestrophins may form chloride ion channels or may regulate voltage-gated L-type calcium-ion channels. Bestrophins are generally believed to form calcium-activated chloride-ion channels in epithelial cells but they have also been shown to be highly permeable to bicarbonate ion transport in retinal tissue. Mutations in this gene are responsible for juvenile-onset vitelliform macular dystrophy (VMD2), also known as Best macular dystrophy, in addition to adult-onset vitelliform macular dystrophy (AVMD) and other retinopathies. Alternative splicing results in multiple variants encoding distinct isoforms.[provided by RefSeq, Nov 2008]

FTH1 (HGNC:3976): (ferritin heavy chain 1) This gene encodes the heavy subunit of ferritin, the major intracellular iron storage protein in prokaryotes and eukaryotes. It is composed of 24 subunits of the heavy and light ferritin chains. Variation in ferritin subunit composition may affect the rates of iron uptake and release in different tissues. A major function of ferritin is the storage of iron in a soluble and nontoxic state. Defects in ferritin proteins are associated with several neurodegenerative diseases. This gene has multiple pseudogenes. Several alternatively spliced transcript variants have been observed, but their biological validity has not been determined. [provided by RefSeq, Jul 2008]

ACMG classification

Verdict is Uncertain_significance. Variant got 0 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (MetaRNN=0.22670558).

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	MANE	UniProt
BEST1	NM_004183.4	c.1006A>G	p.Met336Val	missense_variant	9/11	ENST00000378043.9

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	#exon/exons	TSL	MANE	Appris	UniProt
BEST1	ENST00000378043.9	c.1006A>G	p.Met336Val	missense_variant	9/11	1	NM_004183.4	P1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1460920 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 726660

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: 9.00e-7

Gnomad4 OTH exome AF: 0.00

GnomAD4 genome Cov.: 32

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

Sep 29, 2023

The c.1006A>G (p.M336V) alteration is located in exon 9 (coding exon 8) of the BEST1 gene. This alteration results from a A to G substitution at nucleotide position 1006, causing the methionine (M) at amino acid position 336 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	0.083
BayesDel_addAF	Uncertain	0.15	D
BayesDel_noAF	Uncertain	-0.020
Cadd	Benign	15
Dann	Benign	0.82
DEOGEN2	Benign	0.11	T;.
Eigen	Benign	-0.63
Eigen_PC	Benign	-0.60
FATHMM_MKL	Benign	0.76	D
LIST_S2	Benign	0.84	T;T
M_CAP	Uncertain	0.087	D
MetaRNN	Benign	0.23	T;T
MetaSVM	Benign	-0.29	T
MutationAssessor	Benign	1.6	L;.
MutationTaster	Benign	0.84	D;D;D;D;D;N;N;D;D
PrimateAI	Benign	0.31	T
PROVEAN	Benign	-0.78	N;N
REVEL	Uncertain	0.45
Sift	Benign	0.048	D;T
Sift4G	Benign	0.24	T;T
Polyphen		0.0020	B;B
Vest4		0.13
MutPred		0.34		Loss of disorder (P = 0.0596);.;
MVP		0.88
MPC		0.31
ClinPred		0.071	T
GERP RS		-2.1
Varity_R		0.13
gMVP		0.55

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

No publications associated with this variant yet.

Other links and lift over

hg19: chr11-61727421;