Search Results (991)

Liaoning cashmere goat is a unique Chinese cashmere breed, and skin fibroblast proliferation determines hair follicle development and cashmere quality. Melatonin regulates cutaneous cell activity, and lncRNAs function as ceRNA to sponge miRNAs and modulate target genes. Whether melatonin controls fibroblast proliferation through an lncRNA-miRNA-mRNA cascade remains unclear. This study explored how melatonin mediates the LncRNA16913.1-chi-miR-195-5p-FZD6 axis to regulate cashmere goat skin fibroblast proliferation. We constructed gain-of-function and loss-of-function models of LncRNA16913.1 and chi-miR-195-5p. Immunohistochemistry located FZD6 in hair follicles; RT-qPCR, Western blot, CCK-8, EdU and flow cytometry detected gene expression and cell phenotypes. Bioinformatic prediction, dual-luciferase assay, fluorescence in situ hybridization, RNA pull-down and rescue tests verified molecular binding relationships. Melatonin upregulated LncRNA16913.1 and FZD6, yet downregulated chi-miR-195-5p, with FZD6 mainly distributed in hair follicle inner and outer root sheaths. Inhibiting chi-miR-195-5p boosted fibroblast proliferation, restrained apoptosis and accelerated the cell cycle. chi-miR-195-5p directly suppressed FZD6, while cytoplasmic LncRNA16913.1 sequestered this miRNA to recover FZD6 expression. Silencing LncRNA16913.1 eliminated melatonin-mediated FZD6 upregulation. In short, melatonin increased LncRNA16913.1, which sequestered chi-miR-195-5p to release FZD6 and facilitate fibro-blast proliferation. Combined dual-luciferase, bidirectional rescue and cellular phenotypic assays collectively verified the fact that FZD6 acts as the functional downstream target of chi-miR-195-5p to mediate fibroblast proliferation in vitro. Full article

Background: Esophageal squamous cell carcinoma (ESCC) is an aggressive malignancy with a poor prognosis, highlighting the urgent need to elucidate its molecular mechanisms to develop targeted therapies. Long non-coding RNAs (lncRNAs) play a critical role in cancer progression. However, the majority of lncRNAs involved in ESCC progression remain to be elucidated. Methods: We integrated bioinformatic analyses of the TCGA and GEO datasets to identify differentially expressed lncRNAs in ESCC, and the biological functions of the candidate lncRNA LINC01446 were investigated using loss-of-function assays in ESCC cell lines, including colony formation, wound healing, Transwell invasion, C11-BODIPY staining, malondialdehyde (MDA) quantification, and glutathione (GSH) evaluation. A nude mouse xenograft model was established for in vivo validation, and the underlying molecular mechanism was explored through RNA sequencing, fluorescence in situ hybridization (FISH), dual-luciferase reporter assays, AGO2-RIP, and rescue experiments. Results: LINC01446 was significantly upregulated in ESCC tissues and cell lines. Based on univariate analysis, high expression of LINC01446 was associated with poorer overall survival (OS). Functional studies showed that LINC01446 knockdown suppressed ESCC cell proliferation, migration, and invasion, promoted ferroptosis-related changes in vitro and was associated with increased lipid peroxidation and possible ferroptosis-related changes in vivo. Mechanistic analyses supported a regulatory relationship in which LINC01446 may function as a competing endogenous RNA (ceRNA) for miR-338-3p, thereby contributing to the upregulation of its downstream target, apurinic/apyrimidinic endodeoxyribonuclease 1 (APEX1), in ESCC cells. Moreover, APEX1 was found to be overexpressed in ESCC and associated with poor OS. Conclusions: This study suggests that the LINC01446/miR-338-3p/APEX1 regulatory axis may contribute to ESCC progression and ferroptosis-related regulation. Additionally, LINC01446 and APEX1 represent promising prognostic biomarkers and therapeutic targets for ESCC. Full article

Amplification of MDM2 is the molecular hallmark of atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL) and dedifferentiated liposarcoma (DDL). While fluorescence in situ hybridization (FISH) is widely used for diagnosis, the diagnostic and prognostic value of droplet digital PCR (ddPCR) remains poorly defined. We retrospectively analyzed 341 primary adipocytic tumors, including 85 liposarcomas (22 DDL), using ddPCR to quantify MDM2 copy number variation (CNV). Diagnostic performance was compared with FISH, and associations with clinicopathological variables and outcomes were evaluated using non-parametric tests, ROC analysis, survival analysis, and Firth’s penalized Cox models. Comparison with FISH confirmed the diagnostic utility of ddPCR for detecting MDM2 amplification, while quantitative CNV assessment provided additional prognostic information. CNV values were significantly higher in deep-seated and dedifferentiated tumors and were strongly associated with local recurrence. ROC analysis identified a threshold of 16.85 copies predicting both dedifferentiation and recurrence (AUC 0.982 and 0.942, respectively). Patients with CNV ≥ 16.85 copies had significantly shorter recurrence-free and overall survival. In multivariable analysis, high CNV remained an independent predictor of recurrence (HR 36.6, 95% CI 4.0–4914.2). These findings support ddPCR as a robust method for MDM2 assessment and suggest that quantitative MDM2 copy number may improve both diagnosis and risk stratification in liposarcoma. Full article

Trophoblast retrieval from the cervix (TRIC) is a non-invasive approach that enables access to fetal-derived extravillous trophoblast (EVT) cells as early as the first trimester of pregnancy, offering a unique opportunity for early placental and fetal assessment. Although TRIC has been reported to be feasible between 5 and 20 weeks of gestation, systematic evaluation of EVT recovery across early gestation using complementary analytical approaches remains limited. This study aimed to provide a multi-method assessment of EVT recovery across early gestation. Endocervical samples were collected from 53 pregnant women between 5 and 19 weeks of gestation. EVT cells were isolated by immunomagnetic separation using human leukocyte antigen-G (HLA-G)-specific antibodies and assessed by β-hCG immunofluorescence, fluorescence in situ hybridization (FISH) and fluorescence-activated cell sorting (FACS). Immunofluorescence and FISH analyses showed no significant differences in β-hCG-positive or fetal cell proportions among gestational age groups, supporting stable TRIC-based recovery across early gestation. Exploratory FACS analyses identified HLA-G-positive trophoblast populations, including in samples obtained at 5 weeks of gestation. Because FACS analyses were performed in a subset of the cohort, these findings should be considered exploratory and require validation in larger cohort-wide studies. Overall, our findings support the feasibility of TRIC throughout early gestation and confirm the successful recovery of fetal-derived EVT cells from as early as 5 weeks of gestation. Further studies using larger cohorts and standardized quantitative approaches are required to more comprehensively characterize EVT recovery across early gestation and to optimize the application of TRIC in placental and prenatal research. Full article

In vertebrates, circulating and tissue-resident immune cells contribute to host defense and tissue homeostasis. Their balance is maintained through hematopoiesis and anatomical reservoirs. In mollusks, this balancing is poorly investigated. Thus, the dynamics of circulating and tissue-resident hemocytes after a hemolymph withdrawal were analyzed in Pomacea canaliculata, a snail that allows repeated hemolymph withdrawals and possesses posterior kidney (PK) cell aggregates known as hemocyte islets. In the absence of specific hemocyte markers, flow cytometry data revealed dynamic changes in circulating hemocyte number and populations within 48 h following hemolymph withdrawal. In addition, computer-assisted image analysis of histological sections showed a significant transient reduction in PK hemocyte-islet area. Analyses of publicly available P. canaliculata transcriptomes revealed predominant and highly variable expression of two hematopoiesis-related genes, namely Transglutaminase (PcTGase) and Hematopoietically expressed homeobox protein (PcHhex), in circulating hemocytes and PK. Fluorescence in situ hybridization highlighted constitutive PcTGase and PcHhex expression within PK hemocyte islets. RT-qPCR experiments confirmed transcriptomic data on PcTGase and PcHhex constitutive expression, without significant modulation following hemolymph withdrawal. Collectively, these findings provide the first evidence of parallel recovery dynamics involving circulating hemocytes and PK hemocyte islets in P. canaliculata. Full article

LncRNA NR_003508 has been implicated in lipopolysaccharide (LPS)-induced acute respiratory distress syndrome. Yet, the involvement of LncRNA NR_003508 in Pseudomonas aeruginosa (PA)-induced autophagy remains elusive. This study aims to reveal the underlying mechanisms of LncRNA NR_003508 in PA-induced autophagy, thereby enhancing the basic research content of the pathogenesis of PA infection. Fluorescence in situ hybridization (FISH) probes and q-PCR revealed that PA infection induced macrophage autophagy accompanied by increasing LncRNA NR_003508, suggesting that LncRNA NR_003508 may participate in competing endogenous RNA (ceRNA)-mediated regulatory networks. Concurrently, autophagic clearance of PA requires LncRNA NR_003508. Then, we used the Gene Expression Omnibus (GEO) database to find that LC3 was considered a core protein in PA-infected autophagy. Furthermore, LncRNA NR_003508 promoted the formation of autophagosomes, which played a positive role in PA clearance. Functionally, bioinformatics analysis and luciferase reporter assays demonstrated that LncRNA NR_003508 promotes the conversion of LC3I to LC3II by sponging miR-344i and facilitates p62 degradation by binding to miR-344g-5p. Taken together, our data established that LncRNA NR_003508 enhanced the formation of autophagosomes induced by PA infection via the miR-344i/LC3 and miR-344g-5p/p62 axes, partly boosting the clearance of PA and providing a theoretical basis and experimental support for understanding the mechanisms underlying PA infection. Full article

(1) Background: Over the past few decades, the number and chromosomal arrangement of rDNA loci have been successfully used as cytogenetic markers in comparative studies of many insect taxa, including the hemipteran suborder Heteroptera (or true bugs). Of the seven generally accepted infraorders of true bugs, such data are available only for three: one of the early branching infraorders Nepomorpha and the sister infraorders Cimicomorpha and Pentatomomorpha. To address this gap, we obtained rDNA-FISH data for another “early” evolutionary lineage of true bugs, the infraorder Gerromorpha, in which we studied four species belonging to the families Gerridae and Mesoveliidae. (2) Methods: Standard karyotypes were studied using the Schiff–Giemsa method. To study the chromosomal distribution of the major rDNA (45S rDNA), the Fluorescence In Situ Hybridization (FISH) method was used with an 18S rDNA probe. (3) Results: Three variants of the chromosomal arrangement of 18S rDNA were identified in the studied species. The rDNA loci were located on one pair of autosomes in Aquarius paludum (n = 11AA + X) and Gerris lacustris (n = 10AA + X); on one pair of autosomes and on the X chromosome in Limnoporus rufoscutellatus (n = 10AA + X) (Gerridae); on one of the four X chromosomes and on the Y chromosome in Mesovelia furcata (n = 15AA + X₁X₂X₃X₄Y) (Mesoveliidae). The karyotype of L. rufoscutellatus was studied for the first time. (4) Conclusions: Our study provides the first data on the rDNA-FISH location for the infraorder Gerromorpha and expands current understanding of the chromosomal distribution of rDNA arrays in Heteroptera as a whole. Full article

Brewer’s spent grain (BSG), the main by-product of the brewing industry, is a rich source of arabinoxylans (AXs) and hydroxycinnamic acids, particularly ferulic acid (FA), which contribute to its prebiotic potential. This study evaluates the prebiotic properties of residual solid from an enzymatically treated BSG, compared to the properties of BSG as a non-enzymatically hydrolyzed control. Although the residual solid exhibited total polyphenol (2581.96 ± 70.63 mg/100 g dry weight) and FA (180.84 ± 3.28 mg/100 g dry weight) contents comparable to those of the non-hydrolyzed control (2500.38 ± 284.20 and 179.59 ± 3.30 mg/100 g dry weight, respectively), the AX content was significantly higher (14,084.81 ± 185.72 mg/100 g), accompanied by a lower degree of feruloylation (12.84 ± 0.23 mg FA/g AX), higher antioxidant activity (64,825.35 ± 4011.24 μmol TE/100 g), and structural changes visualized by scanning electron microscopy. In addition, in vitro colonic fermentation showed a delayed butyrogenic profile, with increased butyrate production compared to the control (3.17 ± 1.44 mM). Microbiota analysis by fluorescence in situ hybridization (FISH) coupled with flow cytometry indicated an increase in butyrate-producing bacteria, including Faecalibacterium prausnitzii (+5.90) and Eubacterium rectale (+6.88). Growth of Bacteroides, Lactobacillus, and Bifidobacterium spp. was also promoted. Overall, these findings suggest that enzymatic processing of BSG can generate a residual solid with modified structural characteristics and potential prebiotic functionality, supporting its potential application as a fermentable flour ingredient in functional foods. Full article

A 54-year-old female patient presented with a gradually enlarging mass on the ulnar side of the left wrist. Magnetic resonance imaging demonstrated a fat-containing lesion deep within the flexor carpi ulnaris that showed heterogeneous signal intensity, as well as weak internal and peripheral enhancement, which are not typical for atypical spindle cell/pleomorphic lipomatous tumors (ASPLTs). The imaging appearance overlapped with spindle cell lipoma (SCL), atypical lipomatous tumor/well-differentiated liposarcoma (ALT/WDL), and hibernoma, which made preoperative diagnosis challenging. The mass was excised en bloc. Histologically, the tumor consisted of mature adipocytes with substantial size variation, mild atypical spindle cells within a myxoid stroma, and scattered lipoblasts. Immunohistochemistry showed CD34 positivity and loss of RB1, while MDM2 amplification was absent on fluorescence in situ hybridization analysis, supporting a diagnosis of ASPLT. ASPLT is known for its broad range of morphological and radiological presentations, and this case further highlights the difficulty inherent in distinguishing it from SCL and ALT/WDL based on imaging alone. Recognition of its diverse features and the use of molecular testing are essential for accurately diagnosing ASPLT. Surgical excision remains the standard treatment. Although recurrence has been reported, metastasis of ASPLT is exceedingly rare. Full article

Pediatric acute myeloid leukemia (AML) is biologically heterogeneous, and genomic profiling increasingly informs risk stratification and treatment. We evaluated the relationship between induction response, genomic risk, transplant allocation, and survival in pediatric AML. We retrospectively analyzed 38 pediatric patients with newly diagnosed AML, treated between 2020 and 2025. Clinical, cytogenetic, molecular, treatment, and outcome data were collected. Genomic alterations were assessed using cytogenetics, fluorescence in situ hybridization (FISH), molecular testing, and next-generation sequencing (NGS). Survival was estimated by Kaplan–Meier analysis, and prognostic factors for event-free survival (EFS) were assessed using univariable Cox regression. This study is exploratory given the limited sample size and should be interpreted accordingly. Complete remission (CR) after the first course of induction was achieved in 25/38 patients (65.8%), partial remission (PR) in 3/38 (7.9%), and refractory disease in 10/38 (26.3%). Twenty-four patients underwent allogeneic hematopoietic stem cell transplantation; 17/24 (70.8%) were alive at last follow-up, with a 2-year overall survival rate of 72.9%. Both induction response and genomic risk stratification showed suggestive associations with outcome; descriptively, induction response showed the strongest prognostic discrimination, with achievement of CR associated with markedly improved survival. High cytogenetic risk and FLT3-ITD were significantly associated with inferior EFS. Post-induction measurable residual disease (MRD) positivity was detected in 16 of 38 patients (42.1%) and was associated with suboptimal induction response; MRD negativity did not uniformly preclude adverse outcomes, particularly in the high-risk genomic subgroup. Genomic profiling refined biological risk and post-remission treatment allocation. Integrated assessment of genomic risk, induction response, and MRD status may improve therapeutic stratification in pediatric AML. Full article

Background/Objectives: The Y chromosome plays a crucial role in male fertility, sex determination, and spermatogenesis, yet it remains poorly characterized in Mediterranean river buffalo (Bubalus bubalis, 2n = 50) because of its high repeat content, extensive heterochromatin, and complex palindromic structures. Although a chromosome-level Y assembly is available for swamp buffalo (2n = 48), no equivalent reference exists for the river type. Methods: To address this gap, Y chromosomes from 10 Mediterranean buffalo bulls were isolated by laser microdissection following peripheral blood culture and whole-chromosome amplification. Probe specificity was verified by FISH, and amplified Y chromosomes were sequenced using Illumina NovaSeq 6000 (Illumina, San Diego, CA, USA). Sequencing data were assembled and analysed through de novo assembly, repeat identification, sequence alignment, and variant detection. Comparative analyses included alignment to the swamp buffalo Y chromosome and annotation of Y-linked genes using the Bos taurus reference genome. Results: FISH confirmed the specificity of the isolated material, showing strong signals on the Y chromosome and on X/Y PAR and heterochromatic regions. Sequencing generated over 240 million paired-end reads, and de novo assembly produced 566,815 contigs. Repeat analysis identified 3.91% repetitive elements, mainly SINEs, while variant calling detected more than 23,000 variants. Comparative analyses mapped several contigs to the swamp buffalo Y chromosome and Y-linked genes. Annotation against the B. taurus genome identified 26 unique genes, including homologs shared with the X chromosome, and revealed MSY gene duplications, including 10 copies of TSPY and 3 of HSFY. Conclusions: These findings show that laser microdissection with NGS enables effective access to the buffalo Y chromosome, representing a milestone in the characterization of the river type genome, and providing a basis for studies on buffalo male fertility and breeding programs. Full article

Background/Objectives: HER2 overexpression and/or amplification defines a molecularly distinct subset of endometrial carcinomas (ECs) that may benefit from HER2-targeted therapies. However, HER2 testing algorithms remain non-standardized and vary across institutions. This study is a large single-institution audit of EC HER2 testing practices, using both gynecologic (ISGyP) and gastric cancer-specific scoring algorithms at a major academic center with a reference gynecologic oncology service and biomarker laboratory. Methods: HER2 immunohistochemistry (IHC) and whole-slide fluorescence in situ hybridization (FISH) were interpreted by subspecialty breast and gynecologic pathologists, with HER2 IHC performed on 494 tumor samples (2021–2025) and reflex FISH for equivocal cases. Results: Using ISGyP criteria, 15.0% (74/494) of tumors were HER2 IHC 3+, 44.5% (220/494) equivocal (2+), and 40.5% (200/494) were negative (0/1+). Among equivocal cases, 28.2% (58/205) demonstrated ERBB2 amplification, yielding an overall HER2-positive rate of 27.5% (132/480). Re-assessment with gastric scoring criteria demonstrated variability in HER2 classification, with high concordance in cytology specimens (100%) and resections (90.8%; K = 0.842, p < 0.001) but substantially lower concordance in biopsies (60.6%; K = 0.401, p < 0.001), mainly due to reclassification of equivocal cases. Notably, 47.9% (n = 34) of ISGyP-equivocal biopsy specimens were reclassified as HER2 IHC 3+ using gastric biopsy criteria, potentially expanding eligibility for T-DXd therapy. Conclusions: These findings highlight the evolving nature of HER2 testing in EC and demonstrate the significant impact of scoring methodology on HER2 interpretation. Our results support the development of EC-specific HER2 testing guidelines and a dual-reporting approach incorporating both ISGyP and gastric scoring criteria, with selective confirmatory FISH testing, to optimize patient selection for HER2-targeted therapies. Full article

Objective: Our objectives were to describe molecular profiling in a real-life cohort of patients with radioiodine-resistant (RAI-R) differentiated or poorly differentiated thyroid cancer (DTC or PDTC) treated with lenvatinib and to focus on factors potentially influencing the quality of tissue samples for molecular analysis, including the impact of storage time, defined as the interval between tissue collection and molecular testing. Design: We retrospectively included all lenvatinib-treated RAI-R DTC or PDTC patients tested with DNA- and/or RNA-based next-generation sequencing (NGS) in our center, also analyzing the results of fluorescence in situ hybridization (FISH) for RET fusions if the sample did not satisfy quality criteria for RNA-based NGS analysis. We investigated differences in terms of histotype, biopsy site, or storage time between adequate and inadequate samples for RNA-based NGS. Results: At least one gene alteration was detected in 50% of the cohort (18 out of 36 patients); RAS and BRAF were the most frequent mutations, while gene fusions accounted for 5.6% of cases. Tissue samples were more frequently adequate for DNA-based NGS compared to RNA-NGS analysis (93.9% vs. 58.3%, p < 0.001). The median storage time was significantly longer in the case of inadequate samples for RNA-based NGS compared with adequate specimens (41.5 vs. 9.5 months, p = 0.016); samples archived for ≥3 years led more frequently to an inadequate result. Conclusions: Advanced RAI-R TC candidates for systemic therapy often harbor gene alterations. An adequate result was less frequently achieved in cases of RNA-based NGS than in DNA-based NGS, especially if the interval between tissue collection and molecular analysis was longer; nevertheless, the limited cohort size precludes definitive conclusions. Full article

Background/Objectives: High-grade B-cell lymphomas (HGBCLs) with MYC and BCL2 or BCL6 translocations, colloquially referred to as double-hit lymphomas (and abbreviated here to DHL), are aggressive malignancies. Differentiating DHL from non-DHL HGBCLs is important, as DHL patients may benefit from more intensive treatment regimes. We aimed to identify predictive clinicopathological, morphological, and immunophenotypic features that could guide selection of HGBCLs for fluorescence in situ hybridization (FISH), which is expensive and less accessible in some centers. Methods: We conducted a PRISMA systematic review and meta-analysis on 29 studies identified from four databases (PubMed (MEDLINE), Ovid (Embase), Web of Science, and Scopus). We calculated risk ratios (RRs) to compare features between DHL and non-DHL HGBCL and between MYC/BCL2 and MYC/BCL6 DHL patients. Results: DHL patients were associated with higher Ann Arbor stage (RR 1.15, p = 0.028, I² = 38.7%), International Prognostic Index (IPI) score (RR 1.27, p = 0.047, I² = 37.9%), elevated lactate dehydrogenase (RR 1.26, p = 0.012, I² = 34.0%), and germinal center B-cell-like (GCB) immunophenotype (RR 1.21, p = 0.043, I² = 35.8%) compared to non-DHL HGBCL patients. c-Myc immunopositivity, extranodal disease, and bone marrow involvement were more likely in DHL, albeit not reaching statistical significance. Extranodal disease (p = 0.015, I² = 0.0%), central nervous system involvement (p = 0.044, I² = 0.0%), and non-GCB immunophenotype (p = 0.016, I² = 71.1%) were more likely in MYC/BCL6 compared to MYC/BCL2 DHL patients. BCL2 immunopositivity, CD10 immunopositivity, and MUM1 immunonegativity were more likely in MYC/BCL2 DHL, although the differences were not statistically significant. Conclusions: Our results have associated DHL with features of aggressive disease and found GCB immunophenotype as a histopathological feature with statistically significant predictive value for MYC/BCL2 DHL. Heterogeneity within the non-DHL HGBCL group and variation in immunohistochemical cut-off values between studies limited identification of other predictive features. Larger, consistently designed, prospective cohort studies could provide further evidence for a screening strategy for DHL. Full article

Contemporary iterations of avian phylogenies based on multiple genome sequence assemblies assign three major clades: Palaeognathae (mostly ratite birds), Galloanseres (land and waterfowl) and the largest group—Neoaves. The latter two are sister clades representing subdivisions of Neognathae, while Neoaves further subdivide into Columbaves (pigeons/doves/cuckoos/bustards, etc.), Mirandornithes (flamingos/grebes), Telluraves (“higher land birds”, including finches) and the newly recognized Elementaves (e.g., penguins/pelicans/hummingbirds/swifts/cranes/shorebirds). Molecular studies provide clade information, likely divergence timings and a framework from which gross genomic (chromosomal) changes may be mapped. In this review, we consider the patterns of chromosome change that have occurred throughout all avian clades thus far examined, citing studies from standard karyotyping through molecular cytogenetics to whole genome assemblies. Standard karyotyping led to the realization that most chromosomes (particularly the microchromosomes and dot chromosomes) could not be distinguished by classical means. Indeed, cross-species comparisons were difficult, even among the macrochromosomes, because of indistinct banding patterns. Based on fluorescence (or fluorescent) in situ hybridization (FISH), comparative genomics was thence progressed considerably by cross-species chromosome painting (Zoo-FISH) for the macrochromosomes and interspecific mapping of bacterial artificial chromosome (BAC) probes for the microchromosomes. A key finding was that the most studied species, the chicken, fortuitously, has a genomic organization somewhat akin to that of the ancestral karyotype and tends to be the standard from which all others are measured. A notable exception is the fusion of basal chromosome 4 with a smaller chromosome that convergently appears in some other Galliformes, at least one goose and one dove species. While some groups such as Falconiformes (falcons, etc.) and Psittaciformes (parrots, etc.) underwent extensive interchromosomal change, most, broadly speaking, retain a basic karyotype that differs little from bird to bird. Many, e.g., Passeriformes (finches, songbirds, etc.) and Columbiformes (pigeons, doves), do this despite multiple intrachromosomal rearrangements. The complete karyotype and fully established chromosome-level genome assembly of the chicken allow full integration of DNA sequence assembly with karyotype. They further permit cytogenetic studies to be performed using genome assemblies alone alongside cutting-edge long-read sequencing and optical mapping without the need for chromosome preparation. The classic ZW sex-determination system of birds is easily visible in most Neognathae species, but intrachromosomal change in the sex chromosomes is faster than in the autosomes; indeed, there are numerous examples of autosomal fusions and new sex chromosomes formed. Sex chromosomes aside, the classic avian karyotype represents a very successful mode of genome organization established before the emergence of the dinosaurs and perpetuated to this day in their only living descendants. Full article