NM_004183.4:c.874G>C

Variant names:

• chr11-61959504-G-C
• rs886039311
• NM_004183.4:c.874G>C

Variant summary

Our verdict is Pathogenic. The variant received 13 ACMG points: 13P and 0B. PM1 PM2 PM5 PP2 PP3_Strong PP5_Moderate

The NM_004183.4(BEST1):​c.874G>C​(p.Glu292Gln) variant causes a missense change involving the alteration of a conserved nucleotide. The variant was absent in control chromosomes in GnomAD project. In-silico tool predicts a pathogenic outcome for this variant. Variant has been reported in ClinVar as Likely pathogenic (★). Another variant affecting the same amino acid position, but resulting in a different missense (i.e. E292K) has been classified as Likely pathogenic.

• Frequency: Genomes: not found (cov: 32)
• Consequence: BEST1 NM_004183.4 missense
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:1
• Conservation: PhyloP100: 9.79
• Publications: 7 publications found

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]

LOC107984334 (HGNC:):

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]

FTH1 Gene-Disease associations (from GenCC):

• hemochromatosis type 5

  Inheritance: AD, Unknown Classification: MODERATE, SUPPORTIVE, LIMITED Submitted by: Orphanet, Labcorp Genetics (formerly Invitae), Genomics England PanelApp, Ambry Genetics
• neurodegeneration with brain iron accumulation 9

  Inheritance: AD Classification: MODERATE Submitted by: Ambry Genetics

ACMG classification

Our verdict: Pathogenic. The variant received 13 ACMG points.

• PM1: In a hotspot region, there are 23 aminoacids with missense pathogenic changes in the window of +-8 aminoacids around while only 0 benign, 6 uncertain in NM_004183.4
• PM2: Very rare variant in population databases, with high coverage
• PM5: Other missense variant is known to change same aminoacid residue: Variant chr11-61959504-G-A is described in ClinVar as Pathogenic/Likely_pathogenic. ClinVar VariationId is 265047.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.
• PP2: Missense variant in the gene, where a lot of missense mutations are associated with disease in ClinVar. The gene has 209 curated pathogenic missense variants (we use a threshold of 10). The gene has 23 curated benign missense variants. Gene score misZ: 0.61695 (below the threshold of 3.09). Trascript score misZ: 0.88358 (below the threshold of 3.09). GenCC associations: The gene is linked to vitelliform macular dystrophy 2, MRCS syndrome, autosomal recessive bestrophinopathy, autosomal dominant vitreoretinochoroidopathy, retinitis pigmentosa, retinitis pigmentosa 50, inherited retinal dystrophy, adult-onset foveomacular vitelliform dystrophy, nanophthalmia.
• PP3: MetaRNN computational evidence supports a deleterious effect, 0.969
• PP5: Variant 11-61959504-G-C is Pathogenic according to our data. Variant chr11-61959504-G-C is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 544678.Status of the report is criteria_provided_single_submitter, 1 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
BEST1	NM_004183.4	c.874G>C	p.Glu292Gln	missense_variant	Exon 8 of 11	ENST00000378043.9	NP_004174.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
BEST1	ENST00000378043.9	c.874G>C	p.Glu292Gln	missense_variant	Exon 8 of 11	1	NM_004183.4	ENSP00000367282.4

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome Cov.: 31

GnomAD4 genome Cov.: 32

ClinVar

Significance: Likely pathogenic

Submissions summary: Pathogenic:1

Revision: criteria provided, single submitter

Submissions by phenotype

Vitelliform macular dystrophy 2 Pathogenic:1

May 08, 2018

MAGI'S LAB - Medical Genetics Laboratory, MAGI GROUP

Significance: Likely pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

The p.(Glu292Gln) variant in BEST1 has been identified in a proband and his father both affected by Best vitelliform macular dystrophy (BVMD). Application of ACMG guidelines: PM2, absent from controls (or at extremely low frequency if recessive) in Exome Sequencing Project, 1000 Genomes Project, or Exome Aggregation Consortium; PM5, novel missense change at an amino acid residue where a different missense change determined to be pathogenic has been seen before; PP1, cosegregation with disease in multiple affected family members in a gene definitely known to cause the disease. PP3, multiple lines of computational evidence support a deleterious effect on the gene or gene product (conservation, evolutionary, splicing impact, etc.). In summary, the p.(Glu292Gln) variant meets the ACMG criteria to be classified as likely pathogenic. -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
AlphaMissense	Pathogenic	0.62
BayesDel_addAF	Pathogenic	0.51	D
BayesDel_noAF	Pathogenic	0.49
CADD	Pathogenic	29
DANN	Uncertain	0.99
DEOGEN2	Pathogenic	0.88	D;.
Eigen	Uncertain	0.55
Eigen_PC	Uncertain	0.57
FATHMM_MKL	Pathogenic	0.98	D
LIST_S2	Uncertain	0.94	D;D
M_CAP	Uncertain	0.22	D
MetaRNN	Pathogenic	0.97	D;D
MetaSVM	Pathogenic	1.0	D
MutationAssessor	Uncertain	2.6	M;.
PhyloP100		9.8
PrimateAI	Uncertain	0.61	T
PROVEAN	Uncertain	-2.7	D;D
REVEL	Pathogenic	0.88
Sift	Uncertain	0.0060	D;D
Sift4G	Uncertain	0.013	D;D
Polyphen		1.0	D;D
Vest4		0.92
MutPred		0.87		Loss of ubiquitination at K289 (P = 0.1828);.;
MVP		0.98
MPC		0.92
ClinPred		0.99	D
GERP RS		4.9
Varity_R		0.64
gMVP		0.87
Mutation Taster		=0/100	disease causing (ClinVar)

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

Other links and lift over

dbSNP: rs886039311; hg19: chr11-61726976;