rs587776912

Variant names:

• chr17-68542811-T-C
• rs587776912
• NM_017565.4:c.813-2A>G

Variant summary

Our verdict is Pathogenic. The variant received 18 ACMG points: 18P and 0B. PVS1 PM2 PP5_Very_Strong

The NM_017565.4(FAM20A):​c.813-2A>G variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.00000275 in 1,456,268 control chromosomes in the GnomAD database, with no homozygous occurrence. In-silico tool predicts a pathogenic outcome for this variant. 3/3 splice prediction tools predicting alterations to normal splicing. Variant has been reported in ClinVar as Pathogenic (★★).

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 0.0000027 (0 hom.)
• Consequence: FAM20A NM_017565.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Pathogenic criteria provided, multiple submitters, no conflicts P:3
• Conservation: PhyloP100: 7.67
• Publications: 4 publications found

Genes affected

FAM20A (HGNC:23015): (FAM20A golgi associated secretory pathway pseudokinase) This locus encodes a protein that is likely secreted and may function in hematopoiesis. A mutation at this locus has been associated with amelogenesis imperfecta and gingival hyperplasia syndrome. Alternatively spliced transcript variants have been identified. [provided by RefSeq, Aug 2011]

PRKAR1A (HGNC:9388): (protein kinase cAMP-dependent type I regulatory subunit alpha) cAMP is a signaling molecule important for a variety of cellular functions. cAMP exerts its effects by activating the cAMP-dependent protein kinase, which transduces the signal through phosphorylation of different target proteins. The inactive kinase holoenzyme is a tetramer composed of two regulatory and two catalytic subunits. cAMP causes the dissociation of the inactive holoenzyme into a dimer of regulatory subunits bound to four cAMP and two free monomeric catalytic subunits. Four different regulatory subunits and three catalytic subunits have been identified in humans. This gene encodes one of the regulatory subunits. This protein was found to be a tissue-specific extinguisher that down-regulates the expression of seven liver genes in hepatoma x fibroblast hybrids. Mutations in this gene cause Carney complex (CNC). This gene can fuse to the RET protooncogene by gene rearrangement and form the thyroid tumor-specific chimeric oncogene known as PTC2. A nonconventional nuclear localization sequence (NLS) has been found for this protein which suggests a role in DNA replication via the protein serving as a nuclear transport protein for the second subunit of the Replication Factor C (RFC40). Several alternatively spliced transcript variants encoding two different isoforms have been observed. [provided by RefSeq, Jan 2013]

PRKAR1A Gene-Disease associations (from GenCC):

• Acrodysostosis 1 with or without hormone resistance

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, Labcorp Genetics (formerly Invitae), Ambry Genetics
• acrodysostosis with multiple hormone resistance

  Inheritance: AD Classification: DEFINITIVE, SUPPORTIVE Submitted by: Illumina, Orphanet
• Carney complex, type 1

  Inheritance: AD Classification: DEFINITIVE, STRONG Submitted by: G2P, ClinGen, Ambry Genetics, Labcorp Genetics (formerly Invitae)
• pigmented nodular adrenocortical disease, primary, 1

  Inheritance: AD Classification: STRONG, MODERATE Submitted by: Genomics England PanelApp, Ambry Genetics
• acrodysostosis

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• Carney complex

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• familial atrial myxoma

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet
• primary pigmented nodular adrenocortical disease

  Inheritance: AD Classification: SUPPORTIVE Submitted by: Orphanet

ACMG classification

Our verdict: Pathogenic. The variant received 18 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 8.1, offset of -26, new splice context is: actccctgatcatccctcAGatg. 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 17-68542811-T-C is Pathogenic according to our data. Variant chr17-68542811-T-C is described in ClinVar as Pathogenic. ClinVar VariationId is 35476.Status of the report is criteria_provided_multiple_submitters_no_conflicts, 2 stars.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
FAM20A	NM_017565.4	c.813-2A>G		splice_acceptor_variant, intron_variant	Intron 5 of 10	ENST00000592554.2	NP_060035.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
FAM20A	ENST00000592554.2	c.813-2A>G		splice_acceptor_variant, intron_variant	Intron 5 of 10	1	NM_017565.4	ENSP00000468308.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD2 exomes AF: 0.0000119 AC: 3 AN: 251438 AF XY: 0.0000147

Gnomad AFR exome AF: 0.00

Gnomad AMR exome AF: 0.0000867

Gnomad ASJ exome AF: 0.00

Gnomad EAS exome AF: 0.00

Gnomad FIN exome AF: 0.00

Gnomad NFE exome AF: 0.00

Gnomad OTH exome AF: 0.00

GnomAD4 exome AF: 0.00000275 AC: 4 AN: 1456268 Hom.: 0 Cov.: 29 AF XY: 0.00000276 AC XY: 2 AN XY: 724810

African (AFR) AF: 0.00 AC: 0 AN: 33386

American (AMR) AF: 0.0000671 AC: 3 AN: 44720

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26084

East Asian (EAS) AF: 0.00 AC: 0 AN: 39666

South Asian (SAS) AF: 0.00 AC: 0 AN: 86124

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53342

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5758

European-Non Finnish (NFE) AF: 9.03e-7 AC: 1 AN: 1107004

Other (OTH) AF: 0.00 AC: 0 AN: 60184

GnomAD4 genome Cov.: 32

Alfa AF: 0.00 Hom.: 0

ExAC AF: 0.00000824 AC: 1

ClinVar

Significance: Pathogenic

Submissions summary: Pathogenic:3

Revision: criteria provided, multiple submitters, no conflicts

Submissions by phenotype

Amelogenesis imperfecta type 1G Pathogenic:3

Mar 23, 2022

Baylor Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Jan 01, 2012

OMIM

Significance: Pathogenic

Review Status: no assertion criteria provided

Collection Method: literature only

- -

May 10, 2024

Fulgent Genetics, Fulgent Genetics

Significance: Pathogenic

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.49	D
BayesDel_noAF	Pathogenic	0.27
CADD	Pathogenic	33
DANN	Uncertain	1.0
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	1.0
FATHMM_MKL	Uncertain	0.96	D
PhyloP100		7.7
GERP RS		6.0
Mutation Taster		=0/100	disease causing (ClinVar)

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.57		Details are displayed if max score is > 0.2
DS_AL_spliceai		0.57		Position offset: -2

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

Other links and lift over

dbSNP: rs587776912; hg19: chr17-66538952; COSMIC: COSV56836872; COSMIC: COSV56836872;