X-71118820-C-A

Variant names:

• chrX-71118820-C-A
• rs2092281557
• NM_005120.3:c.66C>A

Variant summary

Our verdict is Likely benign. The variant received -3 ACMG points: 2P and 5B. PM2 BP4_Moderate BP6_Moderate BP7

The NM_005120.3(MED12):​c.66C>A​(p.Pro22Pro) variant causes a synonymous 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. Variant has been reported in ClinVar as Likely benign (★). Synonymous variant affecting the same amino acid position (i.e. P22P) has been classified as Likely benign.

• Frequency:
  • Genomes: not found (cov: 21)
  • Exomes 𝑓: 0.0 (0 hom. 0 hem.)
  • Failed GnomAD Quality Control
• Consequence: MED12 NM_005120.3 synonymous
• Clinical Significance: Likely benign criteria provided, single submitter B:1
• Conservation: PhyloP100: -0.731
• Publications: 0 publications found

Genes affected

MED12 (HGNC:11957): (mediator complex subunit 12) The initiation of transcription is controlled in part by a large protein assembly known as the preinitiation complex. A component of this preinitiation complex is a 1.2 MDa protein aggregate called Mediator. This Mediator component binds with a CDK8 subcomplex which contains the protein encoded by this gene, mediator complex subunit 12 (MED12), along with MED13, CDK8 kinase, and cyclin C. The CDK8 subcomplex modulates Mediator-polymerase II interactions and thereby regulates transcription initiation and reinitation rates. The MED12 protein is essential for activating CDK8 kinase. Defects in this gene cause X-linked Opitz-Kaveggia syndrome, also known as FG syndrome, and Lujan-Fryns syndrome. [provided by RefSeq, Aug 2009]

MED12 Gene-Disease associations (from GenCC):

• FG syndrome 1

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Orphanet
• MED12-related intellectual disability syndrome

  Inheritance: XL Classification: DEFINITIVE Submitted by: ClinGen
• X-linked intellectual disability with marfanoid habitus

  Inheritance: XL Classification: DEFINITIVE, STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), G2P, Orphanet
• blepharophimosis - intellectual disability syndrome, MKB type

  Inheritance: XL Classification: STRONG, SUPPORTIVE Submitted by: Labcorp Genetics (formerly Invitae), Orphanet
• cholestasis-pigmentary retinopathy-cleft palate syndrome

  Inheritance: XL Classification: STRONG Submitted by: Labcorp Genetics (formerly Invitae)

ACMG classification

Our verdict: Likely_benign. The variant received -3 ACMG points.

• PM2: Very rare variant in population databases, with high coverage
• BP4: Computational evidence support a benign effect (BayesDel_noAF=-0.2).
• BP6: Variant X-71118820-C-A is Benign according to our data. Variant chrX-71118820-C-A is described in ClinVar as [Likely_benign]. Clinvar id is 1009749.Status of the report is criteria_provided_single_submitter, 1 stars.
• BP7: Synonymous conserved (PhyloP=-0.731 with no splicing effect.

Transcripts

RefSeq

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	MANE	Protein	UniProt
MED12	NM_005120.3	c.66C>A	p.Pro22Pro	synonymous_variant	Exon 1 of 45	ENST00000374080.8	NP_005111.2

Ensembl

Gene	Transcript	HGVSc	HGVSp	Effect	Exon rank	TSL	MANE	Protein	Appris	UniProt
MED12	ENST00000374080.8	c.66C>A	p.Pro22Pro	synonymous_variant	Exon 1 of 45	1	NM_005120.3	ENSP00000363193.3

Frequencies

GnomAD3 genomes Cov.: 21

GnomAD4 exome Data not reliable, filtered out with message: AC0 AF: 0.00 AC: 0 AN: 1097517 Hom.: 0 Cov.: 31 AF XY: 0.00 AC XY: 0 AN XY: 363007

African (AFR) AF: 0.00 AC: 0 AN: 26390

American (AMR) AF: 0.00 AC: 0 AN: 35194

Ashkenazi Jewish (ASJ) AF: 0.00 AC: 0 AN: 19373

East Asian (EAS) AF: 0.00 AC: 0 AN: 30180

South Asian (SAS) AF: 0.00 AC: 0 AN: 54075

European-Finnish (FIN) AF: 0.00 AC: 0 AN: 40373

Middle Eastern (MID) AF: 0.00 AC: 0 AN: 4126

European-Non Finnish (NFE) AF: 0.00 AC: 0 AN: 841770

Other (OTH) AF: 0.00 AC: 0 AN: 46036

GnomAD4 genome Cov.: 21

ClinVar

Significance: Likely benign

Submissions summary: Benign:1

Revision: criteria provided, single submitter

Submissions by phenotype

FG syndrome Benign:1

May 23, 2024

Labcorp Genetics (formerly Invitae), Labcorp

Significance: Likely benign

Review Status: criteria provided, single submitter

Collection Method: clinical testing

- -

Computational scores

Source: dbNSFP v4.3

Name	Calibrated prediction	Score	Prediction
BayesDel_noAF	Benign	-0.20
CADD	Benign	12
DANN	Benign	0.94
PhyloP100		-0.73
PromoterAI		-0.10	Neutral

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: rs2092281557; hg19: chrX-70338670;