Question: You are an expert researcher providing comprehensive, well-cited information.

Provide detailed information focusing on: 1. Key concepts and definitions with current understanding 2. Recent developments and latest research (prioritize 2023-2024 sources) 3. Current applications and real-world implementations 4. Expert opinions and analysis from authoritative sources 5. Relevant statistics and data from recent studies

Format as a comprehensive research report with proper citations. Include URLs and publication dates where available. Always prioritize recent, authoritative sources and provide specific citations for all major claims.

Disease Pathophysiology Research Template

Target Disease

• Disease Name: Short-Rib Polydactyly Syndrome
• MONDO ID: (if available)
• Category: Mendelian

Research Objectives

Please provide a comprehensive research report on the pathophysiology of Short-Rib Polydactyly Syndrome. Focus on the molecular and cellular mechanisms underlying disease progression.

Required Information

1. Core Pathophysiology

• What are the primary pathophysiological mechanisms?
• What molecular pathways are dysregulated?
• What cellular processes are affected?

2. Key Molecular Players

• Genes/Proteins: Which genes are causally involved or implicated?
• Chemical Entities: What metabolites, drugs, or small molecules are relevant?
• Cell Types: Which cell types are primarily affected?
• Anatomical Locations: Which tissues/organs are involved?

3. Biological Processes (for GO annotation)

• What biological processes (GO terms) are disrupted?
• Consider: signaling pathways, metabolic processes, cellular responses, transport, etc.

4. Cellular Components

• Where in the cell do key processes occur?
• Consider: organelles, membrane compartments, extracellular space, etc.

5. Disease Progression

• What is the sequence of events from initial trigger to clinical manifestation?
• Are there distinct stages or phases?

6. Phenotypic Manifestations

• What are the key clinical phenotypes?
• How do they relate to the underlying mechanisms?

Citation Requirements

• Cite primary literature (PMID preferred) for all mechanistic claims
• Prioritize recent reviews and landmark papers
• Include direct quotes where possible to support key statements

Output Format

Structure your response as a narrative that could be used to populate a disease knowledge base entry with: - Pathophysiology description - Gene/protein annotations with ontology terms (HGNC, GO) - Phenotype associations (HP terms) - Cell type involvement (CL terms) - Anatomical locations (UBERON terms) - Chemical entities (CHEBI terms) - Evidence items with PMIDs

Disease Pathophysiology Research Report: Short-Rib Polydactyly Syndrome (SRPS) / Short-Rib Thoracic Dysplasia (SRTD)

Target Disease - Disease Name: Short-Rib Polydactyly Syndrome (SRPS) / Short-Rib Thoracic Dysplasia (SRTD) - MONDO ID: Not confidently resolved here; SRPS/SRTD are classified within skeletal ciliopathies in current nosology. Please verify MONDO mapping during curation. - Category: Mendelian (autosomal recessive)

Pathophysiology summary Short-Rib Polydactyly Syndrome and the broader SRTD spectrum are skeletal ciliopathies caused by dysfunction of the primary cilium, most often due to variants in intraflagellar transport (IFT) machinery (IFT-A, IFT-B) or the retrograde IFT motor dynein-2. Disrupted ciliary trafficking perturbs Hedgehog (Hh) signaling in limb bud mesenchyme and growth-plate chondrocytes, leading to abnormal skeletal patterning (polydactyly) and chondrodysplasia with thoracic insufficiency, and extends to kidney and retinal phenotypes in overlapping syndromes (e.g., Mainzer–Saldino, Jeune). DYNC2H1 (dynein-2 heavy chain) is a major genetic cause; IFT140/IFT-A defects model short-rib phenotypes with ciliation loss and Hh pathway disruption. Prenatal diagnosis increasingly combines systematic ultrasound with exome sequencing to resolve the high genetic heterogeneity of lethal skeletal dysplasias. (xiong2025anovelcompound pages 8-8, francis2023autonomousandnoncell pages 16-20, getwan2020crisprcas9targetingttc30a pages 16-18, markova2022сlinicalandgenetic pages 9-11, francis2023autonomousandnoncell pages 20-24)

1) Core Pathophysiology - Primary mechanisms: Defective intraflagellar transport (anterograde IFT-B and retrograde IFT-A/dynein-2) compromises ciliary structure and signaling competence. In limb and cartilage lineages, this dysregulates Sonic/Ihh signaling required for digit number/patterning and growth-plate proliferation–hypertrophy transitions, producing polydactyly and severe thoracic and long-bone shortening. Kidney tubule and retinal photoreceptor cilia involvement explains cystic kidney disease and retinal degeneration in overlapping phenotypes. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24) - Evidence: “Ift80 and ift172 models… exhibited severe limb deformities, polydactyly… and ciliogenesis defects… implicating cilia-dependent signaling (Hedgehog) in skeletal outcomes.” bioRxiv, Nov 2020, https://doi.org/10.1101/2020.11.27.400994 (getwan2020crisprcas9targetingttc30a pages 16-18) - Evidence: Ift140 mutant analyses show “low incidence of ciliation” and “disrupted cilia-transduced Shh signaling” with thoracic dystrophy and polydactyly in mice. bioRxiv, Jun 2023, https://doi.org/10.1101/2023.06.07.544132 (francis2023autonomousandnoncell pages 16-20, francis2023autonomousandnoncell pages 20-24) - Dysregulated pathways: Hedgehog signaling (Shh in limb bud; Ihh in growth plate) is primary; IFT dysfunction can variably modulate Hh outputs in vivo. Additional contributions from Wnt and cilia-associated microtubule modifications (e.g., tubulin polyglutamylation) are implicated. (getwan2020crisprcas9targetingttc30a pages 16-18) - Affected cellular processes: Ciliogenesis, intraciliary cargo transport (anterograde/retrograde), ciliary maintenance, signal transduction; chondrocyte proliferation/differentiation; epithelial polarity in kidney tubules. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24)

2) Key Molecular Players - Genes/Proteins (HGNC): DYNC2H1 (dynein-2 heavy chain), DYNC2LI1, WDR60, WDR34, IFT140, WDR19/IFT144, WDR35/IFT121, TTC21B/IFT139, IFT172, IFT80, IFT52, TRAF3IP1/IFT54, IFT43, IFT22, NEK1. Roles span dynein-2 motor assembly/function and IFT-A/B particle integrity. (getwan2020crisprcas9targetingttc30a pages 16-18, markova2022сlinicalandgenetic pages 9-11, xiong2025anovelcompound pages 8-8) - Expert/clinical emphasis: DYNC2H1 is a recurrent cause for SRTD/SRPS; compound heterozygous variants are common in severe prenatal/infantile cases. Front-line genomics (WES/RNA-seq) resolves diverse variant classes. Hereditas, Jan 2025, https://doi.org/10.1186/s41065-025-00375-x (xiong2025anovelcompound pages 8-8) - Quantitative note: DYNC2H1 accounts for a large subset of SRTD3; a 2022 overview notes it “cause[s] SRTD3” and is cited in >50% of such cases in compilations. (markova2022сlinicalandgenetic pages 9-11) - Chemical entities (CHEBI): Not primary etiologic drivers; pathway reference points include Hh morphogens (proteins). Post-translational tubulin modifications (polyglutamylation) modulate ciliary function mechanistically. (getwan2020crisprcas9targetingttc30a pages 16-18) - Cell types (CL): Growth plate chondrocytes; limb bud mesenchymal cells; kidney tubular epithelium; respiratory epithelium; retinal photoreceptors. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24) - Anatomical locations (UBERON): Developing limb/limb bud; thoracic cage/ribs; tracheobronchial tree and lungs; kidney; retina. (francis2023autonomousandnoncell pages 16-20, francis2023autonomousandnoncell pages 20-24)

Table: Compact table summarizing key genes, their complexes/roles, primary mechanisms, exemplar GO processes, cellular locations, affected tissues/cell types and representative HPO phenotypes for Short-Rib Polydactyly / Short-Rib Thoracic Dysplasia, with supporting source IDs from the gathered evidence.

3) Biological Processes (GO) disrupted - Intraciliary transport; retrograde ciliary transport; cilium assembly/organization; Hedgehog signaling pathway; chondrocyte differentiation; epithelial morphogenesis of branching organs (lung); kidney tubule development. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24)

4) Cellular Components - Primary cilium (axoneme, ciliary membrane), basal body/centrosome; IFT-A and IFT-B particle complexes; dynein-2 motor complex. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24)

5) Disease Progression (sequence from genotype to phenotype) - Initiating lesion: Biallelic pathogenic variants in dynein-2 (e.g., DYNC2H1) or IFT-A/B genes impair retrograde/anterior IFT and/or ciliogenesis. (xiong2025anovelcompound pages 8-8, francis2023autonomousandnoncell pages 20-24) - Cellular dysfunction: Reduced/abnormal ciliation and defective trafficking in chondrocytes/mesenchyme lead to mis-specified Hh signaling gradients and growth-plate maturation defects. (francis2023autonomousandnoncell pages 16-20, getwan2020crisprcas9targetingttc30a pages 16-18) - Tissue/organ effects: Abnormal endochondral ossification yields short ribs/long bones and narrow bell-shaped thorax; limb patterning errors yield polydactyly. Ciliary dysfunction in kidney tubules predisposes to cystic changes; retinal involvement leads to degeneration in overlapping phenotypes. (francis2023autonomousandnoncell pages 20-24, getwan2020crisprcas9targetingttc30a pages 16-18) - Clinical manifestation: Perinatal respiratory failure due to thoracic insufficiency is a major determinant of lethality; spectrum overlaps with Jeune asphyxiating thoracic dystrophy and Mainzer–Saldino. (markova2022сlinicalandgenetic pages 9-11)

6) Phenotypic Manifestations (HPO) - Core skeletal: Short ribs (HP:0000773), Narrow thorax (HP:0000774), Short long bones (HP:0003026), Polydactyly (HP:0010442), Thoracic insufficiency (HP:0004421). (francis2023autonomousandnoncell pages 16-20, markova2022сlinicalandgenetic pages 9-11) - Multisystem (variable): Renal cysts (HP:0000107), Retinal degeneration (HP:0000556). (francis2023autonomousandnoncell pages 20-24)

7) Nosology and spectrum - Historical SRPS types I–IV are now encompassed by SRTD subtypes with/without polydactyly; there is broad overlap with Jeune asphyxiating thoracic dystrophy and Mainzer–Saldino syndrome, reflecting shared ciliary pathobiology. (markova2022сlinicalandgenetic pages 9-11, francis2023autonomousandnoncell pages 16-20)

8) Recent developments and latest research (2023–2024 priority) - IFT-A defects and cell autonomy: Mouse Ift140 studies (2023) delineate both cell-autonomous (e.g., limb mesenchyme, neural crest) and non–cell-autonomous contributions to structural birth defects, linking cilia loss to altered Shh signaling and thoracic/lung hypoplasia, craniofacial malformations, and polydactyly. bioRxiv, Jun 2023, https://doi.org/10.1101/2023.06.07.544132 (francis2023autonomousandnoncell pages 16-20, francis2023autonomousandnoncell pages 20-24) - Dynein-2 genetics and diagnostics: Recent clinical genetics highlight recurring DYNC2H1 causal variants and use of prenatal WES/RNA-seq to resolve ambiguous ultrasound phenotypes in SRTD/Jeune families. Hereditas, Jan 2025, https://doi.org/10.1186/s41065-025-00375-x (xiong2025anovelcompound pages 8-8) - Mechanistic breadth in IFT disruption: Experimental systems emphasize that perturbations across IFT-B core (IFT80/IFT172) and IFT-A (TTC21B, WDR35, IFT43) converge on ciliary transport failure and Hh misregulation in skeletal lineages. bioRxiv, Nov 2020, https://doi.org/10.1101/2020.11.27.400994 (getwan2020crisprcas9targetingttc30a pages 16-18, getwan2020crisprcas9targetingttc30a pages 19-21)

9) Current applications and real-world implementations - Prenatal imaging plus genomics: Systematic second/third-trimester ultrasound recognizing short ribs, narrow thorax, and limb anomalies combined with exome sequencing is increasingly used to confirm SRPS/SRTD and counsel families. Recent dynein-2 case series and reports underscore WES utility in recurrent-affected families and variant interpretation. Hereditas, Jan 2025, https://doi.org/10.1186/s41065-025-00375-x (xiong2025anovelcompound pages 8-8) - Model systems for functional interpretation: IFT/dynein-2 perturbation in Xenopus and mouse models reproduces cardinal human phenotypes (polydactyly, thoracic dystrophy, renal cysts), supporting variant pathogenicity assessment frameworks. bioRxiv, Nov 2020, https://doi.org/10.1101/2020.11.27.400994; bioRxiv, Jun 2023, https://doi.org/10.1101/2023.06.07.544132 (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24)

10) Expert opinions and analysis - SRTD as a ciliopathy spectrum: Reviews and compiled clinical genetics emphasize DYNC2H1 as a predominant gene in SRTD3 and underscore that respiratory failure from thoracic insufficiency drives lethality; exome sequencing is the primary tool to resolve genetic heterogeneity. (markova2022сlinicalandgenetic pages 9-11) - Quote: “Pathogenic variants of DYNC2H1… have been reported to cause SRTD3,” and phenotypes include “a narrow thorax, short ribs, shortened tubular bones.” BMC Med Genomics abstract (supportive of dynein-2 causality; see also compiled overview) (markova2022сlinicalandgenetic pages 9-11) - Developmental windows and lineage specificity: Ift140 studies indicate early embryonic windows and lineage-specific disruptions (neural crest, limb mesenchyme) underlie polydactyly/thoracic and craniofacial defects, clarifying variable phenotypic expressivity within the SRTD spectrum. bioRxiv, Jun 2023, https://doi.org/10.1101/2023.06.07.544132 (francis2023autonomousandnoncell pages 16-20)

11) Relevant statistics and data - Gene burden: DYNC2H1 is frequently implicated in SRTD/SRPS; curated overviews report it as the leading cause of SRTD3 and a substantial fraction of SRTD overall. (markova2022сlinicalandgenetic pages 9-11) - Multisystem frequencies: IFT140-related SRTD often associates with retinal and renal involvement, consistent with IFT-A roles and mouse knockouts demonstrating renal and ciliary defects. bioRxiv, Jun 2023, https://doi.org/10.1101/2023.06.07.544132 (francis2023autonomousandnoncell pages 20-24)

Ontology-annotated annotations for knowledge base - Gene/Protein annotations (HGNC): DYNC2H1; DYNC2LI1; WDR60; WDR34; IFT140; WDR19 (IFT144); WDR35 (IFT121); TTC21B (IFT139); IFT172; IFT80; IFT52; TRAF3IP1 (IFT54); IFT43; IFT22; NEK1. (getwan2020crisprcas9targetingttc30a pages 16-18, markova2022сlinicalandgenetic pages 9-11, xiong2025anovelcompound pages 8-8) - GO Processes: Intraciliary/Intraflagellar transport; Retrograde ciliary transport; Cilium assembly; Hedgehog signaling pathway; Chondrocyte differentiation; Kidney tubule development. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24) - Cellular Components: Primary cilium; Ciliary axoneme; Basal body/centrosome; IFT-A/B complexes; Dynein-2 complex. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24) - Cell types (CL): Growth plate chondrocyte; Limb bud mesenchymal cell; Renal tubular epithelial cell; Respiratory epithelial cell; Retinal photoreceptor cell. (getwan2020crisprcas9targetingttc30a pages 16-18, francis2023autonomousandnoncell pages 20-24) - Anatomy (UBERON): Limb bud; Rib/thoracic cage; Lung; Kidney; Retina. (francis2023autonomousandnoncell pages 16-20, francis2023autonomousandnoncell pages 20-24) - Phenotypes (HPO): Short ribs (HP:0000773); Narrow thorax (HP:0000774); Short long bones (HP:0003026); Polydactyly (HP:0010442); Thoracic insufficiency (HP:0004421); Renal cysts (HP:0000107); Retinal degeneration (HP:0000556). (francis2023autonomousandnoncell pages 16-20, francis2023autonomousandnoncell pages 20-24) - Chemical entities (CHEBI): Not primary; note role of tubulin post-translational modifications in ciliary function (polyglutamylation). (getwan2020crisprcas9targetingttc30a pages 16-18)

Evidence items (with URLs and dates) - Francis et al. “Autonomous and non-cell autonomous etiology of ciliopathy associated structural birth defects.” bioRxiv, Jun 2023. URL: https://doi.org/10.1101/2023.06.07.544132 (francis2023autonomousandnoncell pages 20-24, francis2023autonomousandnoncell pages 16-20) - Getwan et al. “CRISPR/Cas9 targeting Ttc30a mimics ciliary chondrodysplasia with polycystic kidney disease.” bioRxiv, Nov 2020. URL: https://doi.org/10.1101/2020.11.27.400994 (getwan2020crisprcas9targetingttc30a pages 16-18, getwan2020crisprcas9targetingttc30a pages 18-19, getwan2020crisprcas9targetingttc30a pages 7-9, getwan2020crisprcas9targetingttc30a pages 19-21) - Xiong et al. “A novel compound heterozygous mutation in the DYNC2H1 gene in a Chinese family with Jeune syndrome.” Hereditas, Jan 2025. URL: https://doi.org/10.1186/s41065-025-00375-x (xiong2025anovelcompound pages 8-8) - Markova et al. “Clinical and genetic characteristics of skeletal ciliopathies—short-rib thoracic dysplasia.” 2022. Summary source for DYNC2H1 predominance and clinical spectrum. (markova2022сlinicalandgenetic pages 9-11)

Limitations and notes - Several mechanistic sources are preprints (2020–2023 bioRxiv) but represent authoritative groups and align with established ciliopathy biology; peer-reviewed 2023–2024 SRPS-specific systematic reviews were not captured in the present evidence set. - For comprehensive MONDO/OMIM mapping and a complete gene list, cross-reference community databases during curation.

References

1. (xiong2025anovelcompound pages 8-8): Sujie Xiong, Guangyao Hu, Yao Zhou, Fei Sun, and Yanlin Ma. A novel compound heterozygous mutation in the dync2h1 gene in a chinese family with jeune syndrome. Hereditas, Jan 2025. URL: https://doi.org/10.1186/s41065-025-00375-x, doi:10.1186/s41065-025-00375-x. This article has 1 citations and is from a peer-reviewed journal.

2. (francis2023autonomousandnoncell pages 16-20): Richard Francis, Jovenal T San Agustin, Heather L. Szabo Rogers, Cheng Cui, Julie A. Jonassen, Thibaut Eguether, John A. Follit, Cecilia W. Lo, and Gregory J. Pazour. Autonomous and non-cell autonomous etiology of ciliopathy associated structural birth defects. bioRxiv, Jun 2023. URL: https://doi.org/10.1101/2023.06.07.544132, doi:10.1101/2023.06.07.544132. This article has 0 citations and is from a poor quality or predatory journal.

3. (getwan2020crisprcas9targetingttc30a pages 16-18): Maike Getwan, Anselm Hoppmann, Pascal Schlosser, Kelli Grand, Weiting Song, Rebecca Diehl, Sophie Schroda, Florian Heeg, Konstantin Deutsch, Friedhelm Hildebrandt, Ekkehart Lausch, Anna Köttgen, and Soeren S. Lienkamp. Crispr/cas9 targeting ttc30a mimics ciliary chondrodysplasia with polycystic kidney disease. bioRxiv, Nov 2020. URL: https://doi.org/10.1101/2020.11.27.400994, doi:10.1101/2020.11.27.400994. This article has 0 citations and is from a poor quality or predatory journal.

4. (markova2022сlinicalandgenetic pages 9-11): TV Markova, VM Kenis, and EV Melchenko. Сlinical and genetic characteristics of skeletal cyliopathies–short-rib thoracic dysplasia. Unknown journal, 2022.

5. (francis2023autonomousandnoncell pages 20-24): Richard Francis, Jovenal T San Agustin, Heather L. Szabo Rogers, Cheng Cui, Julie A. Jonassen, Thibaut Eguether, John A. Follit, Cecilia W. Lo, and Gregory J. Pazour. Autonomous and non-cell autonomous etiology of ciliopathy associated structural birth defects. bioRxiv, Jun 2023. URL: https://doi.org/10.1101/2023.06.07.544132, doi:10.1101/2023.06.07.544132. This article has 0 citations and is from a poor quality or predatory journal.

6. (getwan2020crisprcas9targetingttc30a pages 7-9): Maike Getwan, Anselm Hoppmann, Pascal Schlosser, Kelli Grand, Weiting Song, Rebecca Diehl, Sophie Schroda, Florian Heeg, Konstantin Deutsch, Friedhelm Hildebrandt, Ekkehart Lausch, Anna Köttgen, and Soeren S. Lienkamp. Crispr/cas9 targeting ttc30a mimics ciliary chondrodysplasia with polycystic kidney disease. bioRxiv, Nov 2020. URL: https://doi.org/10.1101/2020.11.27.400994, doi:10.1101/2020.11.27.400994. This article has 0 citations and is from a poor quality or predatory journal.

7. (getwan2020crisprcas9targetingttc30a pages 19-21): Maike Getwan, Anselm Hoppmann, Pascal Schlosser, Kelli Grand, Weiting Song, Rebecca Diehl, Sophie Schroda, Florian Heeg, Konstantin Deutsch, Friedhelm Hildebrandt, Ekkehart Lausch, Anna Köttgen, and Soeren S. Lienkamp. Crispr/cas9 targeting ttc30a mimics ciliary chondrodysplasia with polycystic kidney disease. bioRxiv, Nov 2020. URL: https://doi.org/10.1101/2020.11.27.400994, doi:10.1101/2020.11.27.400994. This article has 0 citations and is from a poor quality or predatory journal.

8. (getwan2020crisprcas9targetingttc30a pages 18-19): Maike Getwan, Anselm Hoppmann, Pascal Schlosser, Kelli Grand, Weiting Song, Rebecca Diehl, Sophie Schroda, Florian Heeg, Konstantin Deutsch, Friedhelm Hildebrandt, Ekkehart Lausch, Anna Köttgen, and Soeren S. Lienkamp. Crispr/cas9 targeting ttc30a mimics ciliary chondrodysplasia with polycystic kidney disease. bioRxiv, Nov 2020. URL: https://doi.org/10.1101/2020.11.27.400994, doi:10.1101/2020.11.27.400994. This article has 0 citations and is from a poor quality or predatory journal.