21-43172082-C-A

Variant names:

• chr21-43172082-C-A
• NM_000394.4:c.324C>A
• CRYAA p.Gly108Gly

Variant summary

Our verdict is Likely benign. The variant received -5 ACMG points: 0P and 5B. BP4_Strong BP7

The NM_000394.4(CRYAA):​c.324C>A​(p.Gly108Gly) variant causes a synonymous change involving the alteration of a non-conserved nucleotide. In-silico tool predicts a benign outcome for this variant. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar. Synonymous variant affecting the same amino acid position (i.e. G108G) has been classified as Benign.

• Frequency: Genomes: not found (cov: 0)
• Consequence: CRYAA NM_000394.4 synonymous
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 0.968
• Publications: 0 publications found

Genes affected

CRYAA (HGNC:2388): (crystallin alpha A) Mammalian lens crystallins are divided into alpha, beta, and gamma families. Alpha crystallins are composed of two gene products: alpha-A and alpha-B, for acidic and basic, respectively. Alpha crystallins can be induced by heat shock and are members of the small heat shock protein (HSP20) family. They act as molecular chaperones although they do not renature proteins and release them in the fashion of a true chaperone; instead they hold them in large soluble aggregates. Post-translational modifications decrease the ability to chaperone. These heterogeneous aggregates consist of 30-40 subunits; the alpha-A and alpha-B subunits have a 3:1 ratio, respectively. Two additional functions of alpha crystallins are an autokinase activity and participation in the intracellular architecture. The encoded protein has been identified as a moonlighting protein based on its ability to perform mechanistically distinct functions. Alpha-A and alpha-B gene products are differentially expressed; alpha-A is preferentially restricted to the lens and alpha-B is expressed widely in many tissues and organs. Defects in this gene cause autosomal dominant congenital cataract (ADCC). [provided by RefSeq, Jan 2014]

CRYAA Gene-Disease associations (from GenCC):

• cataract 9 multiple types

  Inheritance: AD, AR Classification: DEFINITIVE, STRONG Submitted by: Labcorp Genetics (formerly Invitae), G2P, Ambry Genetics
• cataract - microcornea syndrome

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

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

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

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

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Likely_benign. The variant received -5 ACMG points.

• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.52).
• BP7: Synonymous conserved (PhyloP=0.968 with no splicing effect.

Variant Effect in Transcripts

ACMG analysis was done for transcript: NM_000394.4. 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
	CRYAA	NM_000394.4	MANE Select	c.324C>A	p.Gly108Gly	synonymous	Exon 3 of 3	NP_000385.1	P02489
	CRYAA	NM_001363766.1		c.213C>A	p.Gly71Gly	synonymous	Exon 3 of 3	NP_001350695.1	A0A8C8KJZ9

Ensembl Transcripts

Sel.	Gene	Transcript	Tags	HGVSc	HGVSp	Effect	Exon Rank	Protein	UniProt
	CRYAA	ENST00000291554.6	TSL:1 MANE Select	c.324C>A	p.Gly108Gly	synonymous	Exon 3 of 3	ENSP00000291554.2	P02489
	CRYAA	ENST00000398133.5	TSL:3	c.264C>A	p.Gly88Gly	synonymous	Exon 3 of 3	ENSP00000381201.1	E7EWH7
	CRYAA	ENST00000398132.2	TSL:2	c.213C>A	p.Gly71Gly	synonymous	Exon 3 of 3	ENSP00000381200.1	A0A8C8KJZ9

Frequencies

GnomAD3 genomes Cov.: 0

GnomAD4 exome Cov.: 0

GnomAD4 genome Cov.: 0

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.9

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.52
CADD	Benign	13
DANN	Benign	0.76
PhyloP100		0.97

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

MaxEntScan Visualizer can be used to analyze the impact of this mutation on the neighboring sequence.

Other links and lift over

hg19: chr21-44592192;