chr19-19201648-G-C

Variant names:

• chr19-19201648-G-C
• rs2060720733
• NM_176880.6:c.*277C>G

Variant summary

Our verdict is Pathogenic. The variant received 10 ACMG points: 10P and 0B. PVS1 PM2

The NM_003721.4(RFXANK):​c.713-1G>C variant causes a splice acceptor, intron change involving the alteration of a conserved nucleotide. The variant allele was found at a frequency of 0.000000684 in 1,461,786 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. No clinical diagnostic laboratories have submitted clinical-significance assessments for this variant to ClinVar.

• Frequency:
  • Genomes: not found (cov: 32)
  • Exomes 𝑓: 6.8e-7 (0 hom.)
• Consequence: RFXANK NM_003721.4 splice_acceptor, intron
• Scores: Splicing: ADA: 1.000
• Clinical Significance: Not reported in ClinVar
• Conservation: PhyloP100: 8.05
• Publications: 0 publications found

Genes affected

NR2C2AP (HGNC:30763): (nuclear receptor 2C2 associated protein) Located in nucleoplasm. [provided by Alliance of Genome Resources, Apr 2022]

RFXANK (HGNC:9987): (regulatory factor X associated ankyrin containing protein) Major histocompatibility (MHC) class II molecules are transmembrane proteins that have a central role in development and control of the immune system. The protein encoded by this gene, along with regulatory factor X-associated protein and regulatory factor-5, forms a complex that binds to the X box motif of certain MHC class II gene promoters and activates their transcription. Once bound to the promoter, this complex associates with the non-DNA-binding factor MHC class II transactivator, which controls the cell type specificity and inducibility of MHC class II gene expression. This protein contains ankyrin repeats involved in protein-protein interactions. Mutations in this gene have been linked to bare lymphocyte syndrome type II, complementation group B. Multiple alternatively spliced transcript variants encoding different isoforms have been described for this gene. [provided by RefSeq, Jul 2013]

RFXANK Gene-Disease associations (from GenCC):

• MHC class II deficiency

  Inheritance: AR Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Orphanet, ClinGen, Laboratory for Molecular Medicine, Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Pathogenic. The variant received 10 ACMG points.

• PVS1: Splicing +-2 bp (donor or acceptor) variant, LoF is a know mechanism of disease, Cryptic splice site detected, with MaxEntScore 7.8, offset of 8, new splice context is: gccccatctcactgcaacAGgtg. 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

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
NR2C2AP	NM_176880.6	c.*277C>G		3_prime_UTR_variant	Exon 5 of 5	ENST00000331552.12	NP_795361.1
RFXANK	NM_003721.4	c.713-1G>C		splice_acceptor_variant, intron_variant	Intron 9 of 9	ENST00000303088.9	NP_003712.1

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
NR2C2AP	ENST00000331552.12	c.*277C>G		3_prime_UTR_variant	Exon 5 of 5	1	NM_176880.6	ENSP00000332823.6
RFXANK	ENST00000303088.9	c.713-1G>C		splice_acceptor_variant, intron_variant	Intron 9 of 9	1	NM_003721.4	ENSP00000305071.2
NR2C2AP	ENST00000420605.7	c.415-85C>G		intron_variant	Intron 5 of 5	2		ENSP00000402756.1

Frequencies

GnomAD3 genomes Cov.: 32

GnomAD4 exome AF: 6.84e-7 AC: 1 AN: 1461786 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 727206

African (AFR) AF: 0.00 AC: 0 AN: 33480

American (AMR) AF: 0.00 AC: 0 AN: 44724

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 26136

East Asian (EAS) AF: 0.00 AC: 0 AN: 39700

South Asian (SAS) AF: 0.00 AC: 0 AN: 86258

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 53322

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 5768

European-Non Finnish (NFE) AF: 8.99e-7 AC: 1 AN: 1112004

Other (OTH) AF: 0.00 AC: 0 AN: 60394

GnomAD4 genome Cov.: 32

ClinVar

Not reported in ClinVar

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_addAF	Pathogenic	0.63	D
BayesDel_noAF	Uncertain	0.050
CADD	Pathogenic	34
DANN	Uncertain	0.99
Eigen	Pathogenic	1.1
Eigen_PC	Pathogenic	0.88
FATHMM_MKL	Pathogenic	0.97	D
PhyloP100		8.1
GERP RS		4.2
RBP_binding_hub_radar		0.0
RBP_regulation_power_radar		1.6
Mutation Taster		=25/75	disease causing

Splicing

Name	Calibrated prediction	Score	Prediction
dbscSNV1_ADA	Pathogenic	1.0
dbscSNV1_RF	Pathogenic	0.93
SpliceAI score (max)		0.99		Details are displayed if max score is > 0.2
DS_AG_spliceai		0.50		Position offset: 9
DS_AL_spliceai		0.99		Position offset: 1

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

Other links and lift over

dbSNP: rs2060720733; hg19: chr19-19312457;