2-208143069-A-C

Variant names:

• chr2-208143069-A-C
• rs796288
• NM_005210.4:c.253-156T>G

Variant summary

Our verdict is Likely benign. The variant received -2 ACMG points: 2P and 4B. PM2 BP4_Strong

The NM_005210.4(CRYGB):​c.253-156T>G variant causes a intron change involving the alteration of a non-conserved nucleotide. The variant allele was found at a frequency of 0.00000658 in 152,046 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency: Genomes: 𝑓 0.0000066 (0 hom., cov: 32)
• Consequence: CRYGB NM_005210.4 intron
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: -0.319
• Publications: 1 publications found

Genes affected

CRYGB (HGNC:2409): (crystallin gamma B) Crystallins are separated into two classes: taxon-specific, or enzyme, and ubiquitous. The latter class constitutes the major proteins of vertebrate eye lens and maintains the transparency and refractive index of the lens. Since lens central fiber cells lose their nuclei during development, these crystallins are made and then retained throughout life, making them extremely stable proteins. Mammalian lens crystallins are divided into alpha, beta, and gamma families; beta and gamma crystallins are also considered as a superfamily. Alpha and beta families are further divided into acidic and basic groups. Seven protein regions exist in crystallins: four homologous motifs, a connecting peptide, and N- and C-terminal extensions. Gamma-crystallins are a homogeneous group of highly symmetrical, monomeric proteins typically lacking connecting peptides and terminal extensions. They are differentially regulated after early development. Four gamma-crystallin genes (gamma-A through gamma-D) and three pseudogenes (gamma-E, gamma-F, gamma-G) are tandemly organized in a genomic segment as a gene cluster. Whether due to aging or mutations in specific genes, gamma-crystallins have been involved in cataract formation. [provided by RefSeq, Jul 2008]

CRYGB Gene-Disease associations (from GenCC):

• early-onset anterior polar cataract

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• early-onset lamellar cataract

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• total early-onset cataract

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• cataract 39 multiple types

  Inheritance: AD Classification: LIMITED Submitted by: G2P, Labcorp Genetics (formerly Invitae)

ENSG00000295187 (HGNC:):

ACMG classification

Our verdict: Likely_benign. The variant received -2 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.89).

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_005210.4. 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
	CRYGB	NM_005210.4	MANE Select	c.253-156T>G		intron	N/A	NP_005201.2	P07316
	LOC100507443	NR_038437.1		n.221+5890A>C		intron	N/A

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRYGB	ENST00000260988.5	TSL:1 MANE Select	c.253-156T>G		intron	N/A	ENSP00000260988.4	P07316
	ENSG00000295187	ENST00000728538.1		n.224+5890A>C		intron	N/A
	ENSG00000295187	ENST00000728539.1		n.241+5890A>C		intron	N/A

Frequencies

GnomAD3 genomes AF: 0.00000658 AC: 1 AN: 152046 Hom.: 0 Cov.: 32

Gnomad AFR AF: 0.00

Gnomad AMI AF: 0.00

Gnomad AMR AF: 0.00

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: 0.0000147

Gnomad OTH AF: 0.00

We have no GnomAD4 exomes data on this position. Probably position not covered by the project.

GnomAD4 genome AF: 0.00000658 AC: 1 AN: 152046 Hom.: 0 Cov.: 32 AF XY: 0.00 AC XY: 0 AN XY: 74278

African (AFR) AF: 0.00 AC: 0 AN: 41372

American (AMR) AF: 0.00 AC: 0 AN: 15264

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 3472

East Asian (EAS) AF: 0.00 AC: 0 AN: 5194

South Asian (SAS) AF: 0.00 AC: 0 AN: 4830

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 10590

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 316

European-Non Finnish (NFE) AF: 0.0000147 AC: 1 AN: 68006

Other (OTH) AF: 0.00 AC: 0 AN: 2090

Alfa AF: 0.00 Hom.: 612

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.89
CADD	Benign	2.4
DANN	Benign	0.51
PhyloP100		-0.32

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

Other links and lift over

dbSNP: rs796288; hg19: chr2-209007793;