X inactivation, familial skewed, 1

Summary

X inactivation, familial skewed, 1 (MONDO:0026404) is a disease caused by XIST (GenCC Strong), with 1 cohort gene.

At a glance

• Causal gene: XIST (GenCC Strong)
• Cohort genes: 1
• ClinVar variants: 1

Clinical features

No curated clinical features (Orphanet) for this disease.

Identifiers

Disease identifiers

Field	Value
Canonical name	X inactivation, familial skewed, 1
Mondo ID	MONDO:0026404
MeSH	C564716
OMIM	300087
UMLS	C1848138
MedGen	338394
Is cancer (heuristic)	no

Also known as: SXI1 · X inactivation, familial skewed, 1 · X-inactivation, familial skewed · X-inactivation, familial skewed, 1

Data availability: 1 ClinVar variant · 1 GenCC gene-disease record.

Disease family

Classification path: disease › human disease › disease by etiologic mechanism › disease of genetic or genomic mechanism › hereditary disease › X inactivation, familial skewed › X inactivation, familial skewed, 1

Related subtypes (1): X inactivation, familial skewed, 2

Genetics & variants

GWAS landscape

No GWAS associations recorded — common-variant (GWAS) studies don’t cover this disease (typical for Mendelian / rare diseases). See the curated gene cohort and Mendelian overlap below.

Variant details and genetic-evidence tiers

ClinVar germline variants

1 retrieved; paginated sample, class counts are floors:

1 likely pathogenic

ClinVar	Variant (HGVS)	Gene	Classification	Review
9779	NC_000023.11:g.73852757G>C	XIST	Likely pathogenic	criteria provided, single submitter

Genes & proteins

Mendelian disease overlap and somatic drivers

GenCC: 1 · Orphanet: 0 · OMIM-shared: 0 · Dual-evidence (GWAS+Mendelian): 0

GenCC gene–disease validity (cohort genes)

the Disease column is the GenCC-asserted condition — a cohort gene’s strongest validity may be for a related predisposition syndrome.

Gene	Classification	Inheritance	Disease	Records
XIST	Strong	X-linked	X inactivation, familial skewed, 1

Cohort genes → proteins

1 cohort genes, 0 distinct canonical proteins.

Evidence partition

Subset	Genes
multi_evidence	1

Cohort genes (full)

Symbol	HGNC	Ensembl	UniProt	Name	Evidence
XIST	HGNC:12810	ENSG00000229807		X inactive specific transcript	gencc,clinvar

Protein-family classification

Druggable: 0 · Difficult: 0 · Unknown: 1 · Druggable fraction: 0.0

Family distribution

Cohort families vs a genome-wide background (hypergeometric, BH-FDR; fold = observed/expected). Counts kept; sorted by enrichment, so the catch-all Other/Unknown bucket no longer leads.

Family	Genes	Fold	FDR
Other/Unknown	1	1.8×	0.558

Per-gene assignment

Symbol	Family	Druggable?	EC	InterPro (top 3)
XIST	Other/Unknown	no

Expression context

Cohort genes with no expression data: 0.

1 cohort gene are a single-cell marker in ≥1 SCXA experiment.

Breadth distribution (Bgee present_calls)

Bucket	Genes
narrow (1-5 tissues)	0
moderate (6-20)	0
broad (>20)	1
unknown	0

Top tissues across cohort

Tissue	Cohort genes
ileal mucosa	1
skin of hip	1
tibia	1

Per-gene tissue summary (top 30)

Symbol	Bgee breadth	FANTOM5 breadth	SCXA	Top tissues
XIST	244	broad	marker	tibia, skin of hip, ileal mucosa

Protein interactions among cohort

Intra-cohort edges: 0.

Hub genes (top 10 by interactor count)

Symbol	Interactor count
XIST	0

Structural data

PDB: 0 · AlphaFold-only: 0 · No structure: 1

Function

Pathway analysis

Distinct Reactome pathways touched by cohort: 0. Enrichment computed across 1 evidence-associated genes (0 with Reactome annotation).

Therapeutics

Drug target analysis

Approved (phase 4): 0 · Phase ≥3: 0 · Phased (≥1): 0 · Undrugged: 1

Druggability breadth: 0 of 1 evidence-associated genes (0%) have a ChEMBL target (buckets above are over the deeply-mined display cohort).

Top cohort targets by molecule count

Symbol	Molecules	Max phase
XIST	0	0

Bioactivity and enzyme data

Enzyme cohort genes (≥1 EC): 0.

Pharmacogenomics

Cohort genes with a PharmGKB record: 1; with CPIC/DPWG dosing guidelines: 0.

No cohort gene has a CPIC/DPWG genotype-guided dosing guideline (PharmGKB).

Chemical tractability of cohort targets

0 approved/phased compounds have measured bioactivity against a cohort gene (and aren’t yet in disease-level trials). This is a research / tractability signal, NOT a therapeutic recommendation — a bioactivity row often reflects off-target or screening binding (e.g. promiscuous kinase inhibitors against a cohort kinase), implying no disease mechanism.

Druggability pyramid

Cohort genes binned by druggability tier (high → low):

Tier	Definition	Genes	Symbols
A	Approved (phase 4 drug)	0
B	Phased (≥1) drug, not yet approved	0
C	Druggable family + PDB, no drug	0
D	Druggable family + AlphaFold only, no drug	0
E	Difficult family or no structure, no drug	1	XIST

Undrugged target profiles

1 cohort genes are undrugged. Ranked by ‘starting-point quality’ (assay depth + drugged-partner adjacency).

Symbol	ChEMBL assays	Drugged partners (top 3)
XIST	0	—

Clinical trials & evidence

Clinical trials

Clinical trials: 0.