rs1555096248

Variant names:

• chr11-61950428-G-T
• rs1555096248
• NM_004183.4:c.-37+1G>T

Variant summary

Our verdict is Pathogenic. The variant received 12 ACMG points: 12P and 0B. PVS1 PM2 PP5_Moderate

The NM_004183.4(BEST1):​c.-37+1G>T variant causes a splice donor, intron 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. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Likely pathogenic (★).

• Frequency:
  • Genomes: not found (cov: 33)
  • Exomes 𝑓: 0.0 (0 hom.)
  • Failed GnomAD Quality Control
• Consequence: BEST1 NM_004183.4 splice_donor, intron
• Scores: Splicing: ADA: 0.9999
• Clinical Significance: Likely pathogenic criteria provided, single submitter P:2
• Conservation: PhyloP100: 2.46
• Publications: 0 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]

BEST1 Gene-Disease associations (from GenCC):

• autosomal dominant vitreoretinochoroidopathy

  Inheritance: AD Classification: DEFINITIVE, STRONG, MODERATE, SUPPORTIVE Submitted by: Ambry Genetics, Orphanet, G2P, Labcorp Genetics (formerly Invitae)
• BEST1-related dominant retinopathy

  Inheritance: AD Classification: DEFINITIVE Submitted by: ClinGen
• retinitis pigmentosa

  Inheritance: AD, AR Classification: DEFINITIVE, SUPPORTIVE Submitted by: Orphanet, G2P
• vitelliform macular dystrophy 2

  Inheritance: AD Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics, Orphanet
• autosomal recessive bestrophinopathy

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: G2P, Orphanet, Labcorp Genetics (formerly Invitae), Ambry Genetics
• retinitis pigmentosa 50

  Inheritance: AD Classification: STRONG, LIMITED Submitted by: Ambry Genetics, Labcorp Genetics (formerly Invitae)
• adult-onset foveomacular vitelliform dystrophy

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• MRCS syndrome

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• nanophthalmia

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 12 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 6, offset of 11, new splice context is: aagGTgccc. Cryptic site results in frameshift change. If cryptic site found is not functional and variant results in exon loss, it results in frameshift change.
• PM2: Very rare variant in population databases, with high coverage
• PP5: Variant 11-61950428-G-T is Pathogenic according to our data. Variant chr11-61950428-G-T is described in ClinVar as Likely_pathogenic. ClinVar VariationId is 438184.Status of the report is criteria_provided_single_submitter, 1 stars.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_004183.4. 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
	BEST1	NM_004183.4	MANE Select	c.-37+1G>T		splice_donor intron	N/A	NP_004174.1	O76090-1
	BEST1	NM_001440571.1		c.-37+1G>T		splice_donor intron	N/A	NP_001427500.1
	BEST1	NM_001440572.1		c.-37+1G>T		splice_donor intron	N/A	NP_001427501.1

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	BEST1	ENST00000378043.9	TSL:1 MANE Select	c.-37+1G>T		splice_donor intron	N/A	ENSP00000367282.4	O76090-1
	BEST1	ENST00000449131.6	TSL:1	c.-29+1G>T		splice_donor intron	N/A	ENSP00000399709.2	O76090-3
	BEST1	ENST00000534553.5	TSL:2	c.-212+1G>T		splice_donor intron	N/A	ENSP00000431189.1	E9PMB5

Frequencies

GnomAD3 genomes Cov.: 33

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 586 Hom.: 0 Cov.: 0 AF XY: 0.00 AC XY: 0 AN XY: 346

African (AFR) AF: 0.00 AC: 0 AN: 2

American (AMR) AF: 0.00 AC: 0 AN: 2

Ashkenazi Jewish (ASJ) AC: 0 AN: 0

East Asian (EAS) AF: 0.00 AC: 0 AN: 96

South Asian (SAS) AF: 0.00 AC: 0 AN: 2

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 432

Middle Eastern (MID) AC: 0 AN: 0

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 42

Other (OTH) AF: 0.00 AC: 0 AN: 10

GnomAD4 genome Cov.: 33

ClinVar

ClinVar submissions

Significance: Likely pathogenic

Revision: criteria provided, single submitter

Pathogenic	VUS	Benign	Condition
1	-	-	Autosomal recessive bestrophinopathy (1)
1	-	-	Retinal dystrophy (1)

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.12
CADD	Pathogenic	27
DANN	Uncertain	0.99
PhyloP100		2.5
PromoterAI		-0.23	Neutral
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.94
SpliceAI score (max)		0.89		Details are displayed if max score is > 0.2
DS_DG_spliceai		0.23		Position offset: 10
DS_DL_spliceai		0.89		Position offset: -1

Find out detailed SpliceAI scores and Pangolin per-transcript scores at spliceailookup.broadinstitute.org

Other links and lift over

dbSNP: rs1555096248; hg19: chr11-61717900;