A Case of Chimeric Turner Syndrome with Normal Reproductive Function.

BACKGROUND: Turner syndrome (TS) is a common sex chromosome disorder with the highest incidence among chromosomal abnormalities. Most of the patients showed short stature, small uterus, ovarian atrophy with a stringy shape, external genital dysplasia, primary amenorrhea, infertility, breast agenesis, and other symptoms which are important causes of female infertility. METHODS: Peripheral blood lymphocytes were cultured with 1,640 medium for 72 hours. The chromosome karyotypes were counted and analyzed after hypotonic operation, fixation, drop operation, and G-banding operation. RESULTS: The peripheral blood chromosome karyotype of the pregnant woman was 45,X,9qh+[25]/46,XX,9qh+[75]. The case was a patient with chimeric TS, and her chromosome 9 was polymorphic. CONCLUSIONS: The clinical phenotype of patients with chimeric TS cannot be determined solely by chromosome karyotype. The influences of somatic mosaics and X chromosome inactivation and other factors on the clinical phenotype should be considered. This study enriched the theoretical basis for prenatal diagnosis and genetic counseling of chimeric TS.

Clinical Characteristics and Diagnosis of Nonaccelerating MDS/MPN-U Patient with 5q- Karyotype.

BACKGROUND: The aim of the study was to improve the clinical cognition of nonaccelerating myelodysplastic/myeloproliferative neoplasms-unclassifiable (MDS/MPN-U) with 5q- karyotype and to avoid misdiagnosis or delayed diagnosis. METHODS: The clinical manifestations and laboratory results of a patient with nonaccelerating MDS/MPN-U with 5q- karyotype were analyzed, and related literature was reviewed. RESULTS: The patient was admitted to hospital mainly due to chest tightness and shortness of breath, aggravated for 4 days. After admission, combined with clinical manifestations, bone marrow cell morphology, immunology, multiparameter flow cytometry, cytogenetics and molecular biology, etc., the final diagnosis was MDS-MPN-U. CONCLUSIONS: Research on the correlation between MPN-U and MDS with 5q deletion is still needed. Clinically, MPN-U combined with MDS is prone to misdiagnosis. In diagnosing MPN-U patients, it is essential to not only complete routine and immunological tests but also consider clinical manifestations and laboratory results. It is crucial to be vigilant about the possibility of concurrent diseases, especially cancer, and to choose targeted examinations in a timely manner to avoid missed or incorrect diagnoses.

Three genome assemblies of Opsariichthys bidens from Yangzte River, Pearl River and Qiantang River basins.

Opsariichthys bidens is an endemic minnow, mainly distributed in China as an emerging aquaculture species. In this study, O. bidens collected from Yangzte River (YR), Pearl River (PR) and Qiantang River (QR) basins were used for karyotypic study and genome sequencing. Using PacBio long reads and Hi-C data, we assembled high-quality O. bidens genomes of 852.41 Mb (YR), 843.11 Mb (PR) and 840.94 Mb (QR) with scaffold N50 lengths of 21.01 Mb, 23.62 Mb and 24.75 Mb, respectively, of which 90.39%, 95.67% and 99.01% were anchored to 37, 38 and 39 chromosomes, respectively. 26,556 (YR), 25,036 (PR) and 26,283 (QR) protein-coding genes were predicted, respectively. The karyotype of O. bidens from YR, PR and QR were 2 N = 74 (6 m + 6sm + 4st + 58t), 2 N = 76 (4 m + 6sm + 4st + 62t) and 2 N = 78 (4 m + 4sm + 4st + 66t), respectively. Collinearity analysis and telomere predictions indicated that the observed chromosomal evolution was driven by Robertsonian translocation. These genome assemblies facilitate cryptic species determination, evolutionary study and genetic breeding of genus Opsariichthys.

Comparative cytogenetics of three Zoraptera species as a basis for understanding chromosomal evolution in Polyneoptera insects.

Zoraptera (also called "angel insects") is one of the most unexplored insect orders. However, it holds promise for understanding the evolution of insect karyotypes and genome organization given its status as an early branching group of Polyneoptera and Pterygota (winged insects) during the Paleozoic. Here, we provide karyotype descriptions of three Zorapteran species: Brazilozoros huxleyi (2n♂; ♀ = 42; 42), B. kukalovae (2n♂; ♀ = 43; 44) and Latinozoros cacaoensis (2n♂; ♀ = 36; 36). These species represent two of the four recently recognized Zorapteran subfamilies. Contrary to an earlier suggestion that Zoraptera has holocentric chromosomes, we found karyotypes that were always monocentric. Interestingly, we detected both X0 (B. kukalovae) and XY (B. huxleyi, L. cacaoensis) sex chromosome systems. In addition to conventional karyotype descriptions, we applied fluorescent in situ hybridization for the first time in Zoraptera to map karyotype distributions of 18S rDNA, histone H3 genes, telomeres and (CAG)n and (GATA)n microsatellites. This study provides a foundation for cytogenetic research in Zoraptera.

A chromosome-level genome assembly of the Brontispa longissima.

Brontispa longissima is a highly destructive pest that affects coconut and ornamental palm plants. It is widely distributed across Southeast and East Asia and the Pacific region, causing production losses of up to 50-70%. While control methods and ecological phenomena have been the primary focus of research, there is a significant lack of studies on the molecular mechanisms underlying these ecological phenomena. The absence of a reference genome has also hindered the development of new molecular-targeted control technologies. In this study, we conducted a karyotype analysis of B. longissima and assembled the first high-quality chromosome-level genome. The assembled genome is 582.24 Mb in size, with a scaffold N50 size of 63.81 Mb, consisting of 10 chromosomes and a GC content of 33.71%. The BUSCO assessment indicated a completeness estimate of 98.1%. A total of 23,051 protein-coding genes were predicted. Our study provides a valuable genomic resource for understanding the mechanisms of adaptive evolution and facilitates the development of new molecular-targeted control methods for B. longissima.

Prenatal diagnosis and molecular cytogenetic analyses of a homozygous Robertsonian translocation family with novel mosaic Robertsonian fission karyotype.

BACKGROUND: Approximately one person in 1000 is a Robertsonian translocation carrier. Errors in the formation of eggs (or more rarely of sperms) may be the cause of Robertsonian translocation. Most Robertsonian translocation carriers are healthy and have a normal lifespan, but do have an increased risk of offsprings with trisomies and pregnancy loss. The fitness of Robertsonian translocation carriers is reduced, but can provide material for evolution. MATERIALS AND METHODS: We have done prenatal diagnosis and molecular cytogenetic analyses on this homozygous Robertson translocation family. We report a homozygous Robertson translocation family with previously undescribed mosaic Robertsonian fission karyotype. RESULTS: We identified six Robertsonian translocation carriers in this family. Four were heterozygous translocation carriers of 45,XX or XY,der(14;15)(q10;q10), one was a homozygous translocation carrier of a 44,XY,der(14;15)(q10;q10),der(14;15)(q10;q10), and one was a previously undescribed Robertsonian fission carrier of 45,XN,der(14;15)(q10;q10)[42]/46,XN[58] with normal phenotype. CONCLUSION: We reported a previously undescribed mosaic Robertsonian fission karyotype. The homozygosity of Robertsonian translocation for speciation may be a potential mechanism of speciation in humans. In theory, the carriers of homologous Robertsonian translocation cannot produce normal gametes, but Robertson fission made it possible for them to produce normal gametes.

Chromosome-level genome assemblies of two littorinid marine snails indicate genetic basis of intertidal adaptation and ancient karyotype evolved from bilaterian ancestors.

Living in the intertidal environment, littorinid snails are excellent models for understanding genetic mechanisms underlying adaptation to harsh fluctuating environments. Furthermore, the karyotypes of littorinid snails, with the same chromosome number as the presumed bilaterian ancestor, make them valuable for investigating karyotype evolution from the bilaterian ancestor to mollusks. Here, we generated high-quality, chromosome-scale genome assemblies for 2 littorinid marine snails, Littorina brevicula (927.94 Mb) and Littoraria sinensis (882.51 Mb), with contig N50 of 3.43 Mb and 2.31 Mb, respectively. Comparative genomic analyses identified 92 expanded gene families and 85 positively selected genes as potential candidates possibly associated with intertidal adaptation in the littorinid lineage, which were functionally enriched in stimulus responses, innate immunity, and apoptosis process regulation and might be involved in cellular homeostasis maintenance in stressful intertidal environments. Genome macrosynteny analyses indicated that 4 fissions and 4 fusions led to the evolution from the 17 presumed bilaterian ancestral chromosomes to the 17 littorinid chromosomes, implying that the littorinid snails have a highly conserved karyotype with the bilaterian ancestor. Based on the most parsimonious reconstruction of the common ancestral karyotype of scallops and littorinid snails, 3 chromosomal fissions and 1 chromosomal fusion from the bilaterian ancient linkage groups were shared by the bivalve scallop and gastropoda littorinid snails, indicating that the chromosome-scale ancient gene linkages were generally preserved in the mollusk genomes for over 500 million years. The highly conserved karyotype makes the littorinid snail genomes valuable resources for understanding early bilaterian evolution and biology.

[Clinical characteristics and management status of Turner syndrome in 1 089 children].

Objective: To investigate the clinical characteristics and management status of children with Turner syndrome (TS) in China. Methods: As a cross-sectional study, 1 089 TS patients were included in the database of the National Collaborative Alliance for the Diagnosis and Treatment of Turner Syndrome from August 2019 to November 2023. Clinical characteristics (growth development, sexual development, organ anomalies, etc.), karyotypes, auxiliary examinations, and treatments were collected and analyzed. Results: Among the 1 089 TS cases, 809 were recorded karyotypes. The karyotype distribution was as follows: 45, X in 317 cases (39.2%), X chromosome structural variants (including partial deletions of p or q arm, ring chromosome, and marker chromosome) in 89 cases (11.0%), 45, X/46, XX mosaicism in 158 cases (19.5%), mosaicism with X chromosome structural variants in 209 cases (25.8%), and presence of Y chromosome material in 36 cases (4.4%). Among the 824 TS cases, the age of diagnosis was 9.7(6.4, 12.2) years, with a height standard deviation score (HtSDS) of -3.1±1.2. Five hundred and fifty three cases underwent growth hormone (GH) stimulation test, and 352 cases (63.7%) had GH peak values <10 µg/L and 75.9% (577/760) had low IGF1 levels, with IGF1 SDS ≤-2 accounting for 38.2% (290 cases). Among 471 cases aged ≥8 years, 132 cases (28.0%) showed spontaneous sexual development (mean bone age (11.0±1.7) years), 10 cases had spontaneous menarche (mean bone age (12.0±2.2) years), and 2 cases had regular menstrual cycles. Common physical features included cubitus valgus (311 cases (28.5%)), neck webbing (188 cases (17.2%)), low posterior hairline (185 cases (17.0%)), shield chest (153 cases (14.0%)), high arched palate (127 cases (11.6%)), short fourth metacarpal (43 cases (3.9%)), and spinal abnormalities (38 cases (3.5%)). Congenital cardiovascular and urogenital anomalies occurred in 91 cases (19.4%) and 66 cases (12.0%)respectively. Abdominal ultrasound in 33 cases (7.2%) indicated fatty liver, hepatomegaly, intrahepatic bile duct stones, and splenomegaly. Among 23 cases undergoing oral glucose tolerance test (OGTT) test, 2 were diagnosed with diabetes mellitus and 4 with impaired glucose tolerance. Following diagnosis, 669 cases (80.7%) received rhGH treatment at a chronological age of (9±4) years and bone age of (8.3±3.2) years. Additionally, 112 cases (19.4%) received sex hormone replacement therapy starting at the age of (14±4) years and bone age of (12.6±1.2) years. Conclusions: The karyotypes of 45, X and mosaicism were most common in Chinese children with TS. The clinical manifestations were mainly short stature and gonadal dysplasia. However, a few TS children could be in the normal range of height, and some cases among those aged of ≥8 years old had spontaneous sexual development. Some exhibited physical features, congenital cardiovascular and urogenital anomalies, and dysfunction of the hypothalamic-pituitary-IGF1 axis. Moreover, a few of them developed impaired glucose tolerance and diabetes mellitus. Following diagnosis, most of the patients received rhGH treatment, and a few of them received sex hormone replacement therapy.

The chromosome number and heterochromatin distribution pattern suggest differentiation among species of the Stylosanthes scabra-seabrana complex.

The genus Stylosanthes has economic importance in semi-arid regions and requires studies that reveal complex relationships between species involving different ploidies. The aim of this study was to cytogenetically investigate accessions of Stylosanthes identified as S. scabra, in order to properly identify the number, morphology, and pattern of distribution of heterochromatin, analyzing the karyological variability of these species. Accessions with 2n=40 and 2n=20 were identified, exhibiting semi-reticulate interphase nuclei, symmetric karyotype, varied morphology, with differences in average chromosomal size, and genome length. The analysis with the fluorochromes chromomycin (CMA) and 4',6-diamidino-2-phenylindole (DAPI) allowed the visualization of two CMA+ blocks in the subterminal region of the short arm in all accessions, and DAPI+/CMA- bands in S. scabra accessions. This suggests that not only chromosomal rearrangements, but also changes in the composition of heterochromatin, may have occurred during the speciation of this genus, and that S. scabra may be undergoing chromosomal evolution based on the observed karyological differences. In addition to the ploidy level, the distribution pattern of CMA+ heterochromatin reinforces the separation between S. scabra and S. seabrana. Thus, this genus represents an interesting group of plants for further studies on the content and quantity of repetitive and non-repetitive DNA sequences.

Chromosome-level genome assembly of the morabine grasshopper Vandiemenella viatica19.

Morabine grasshoppers in the Vandiemenella viatica species group, which show karyotype diversity, have been studied for their ecological distribution and speciation in relation to their genetic and chromosomal diversity. They are good models for studying sex chromosome evolution as "old" and newly emerged sex chromosomes co-exist within the group. Here we present a reference genome for the viatica19 chromosomal race, that possesses the ancestral karyotype within the group. Using PacBio HiFi and Hi-C sequencing, we generated a chromosome-level assembly of 4.09 Gb in span, scaffold N50 of 429 Mb, and complete BUSCO score of 98.1%, containing 10 pseudo-chromosomes. We provide Illumina datasets of males and females, used to identify the X chromosome. The assembly contains 19,034 predicted protein-coding genes, and a total of 75.21% of repetitive DNA sequences. By leveraging HiFi reads, we mapped the genome-wide distribution of methylated bases (5mC and 6 mA). This comprehensive assembly offers a robust reference for morabine grasshoppers and supports further research into speciation and sex chromosome diversification within the group and its related species.

Mosaic distal 13q duplication due to mosaic unbalanced translocation of 46,XY,der(14)t(13;14)(q32.2;p13)/46,XY at amniocentesis in a pregnancy associated with a favorable fetal outcome, perinatal progressive decrease of the aneuploid cell line and cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes.

OBJECTIVE: We present mosaic distal 13q duplication due to mosaic unbalanced translocation 46,XY,der(14)t(13;14)(q32.2;p13)/46,XY at amniocentesis in a pregnancy associated with a favorable fetal outcome. CASE REPORT: A 37-year-old, gravida 2, para 0, woman underwent amniocentesis at 17 weeks of gestation because of advanced maternal age. Amniocentesis revealed a karyotype of 46,XY, add(14) (p13)[17]/46,XY[13] (56.6% mosaicism). Array comparative genomic hybridization (aCGH) analysis on the DNA extracted from cultured amniocytes revealed arr 13q32.2q34 × 2∼3, consistent with 45% mosaicism for distal 13q duplication. Repeat amniocentesis at 24 weeks of gestation revealed a karyotype of 46,XY,der(14)t(13;14)(q32.2;p13)[14]/46,XY[16] (46.6% mosaicism). The parental karyotypes were normal. aCGH analysis on the DNA extracted from uncultured amniocytes revealed arr 13q32.2q34 × 2.38, consistent with 30-40% mosaicism for distal 13q duplication. Interphase fluorescence in situ hybridization (FISH) analysis on uncultured amniocytes detected 22.8% (23/101 cells) mosaicism for distal 13q duplication. Prenatal ultrasound findings were unremarkable. At 39 weeks of gestation, a 3616-g phenotypically normal baby was delivered. The karyotypes of cord blood, umbilical cord and placenta were 46,XY,der(14)t(13;14)(q32.2;p13)[20]/46,XY[20] (50% mosaicism), 46,XY,der(14)t(13;14)(q32.2;p13)[14]/46,XY[26] (35% mosaicism) and 46,XY (40/40 cells) (0% mosaicism), respectively. When follow-ups at the age of 4½ months and the age of one year, the peripheral blood had the karyotype of 46,XY,der(14)t(13;14)(q32.2;p13)[18]/46,XY[22] (45% mosaicism). Interphase FISH analysis on buccal mucosal cells at the age of 4½ months revealed 2.7% (3/110 cells) mosaicism for distal 13q duplication, compared with 1% (1/100 cells) in the normal control. The neonate was normal in phenotype and development. CONCLUSIONS: Mosaic unbalanced translocation at amniocentesis can be associated with a favorable fetal outcome, perinatal progressive decrease of the aneuploid cell line and cytogenetic discrepancy between cultured amniocytes and uncultured amniocytes.

Continued decitabine/all-trans retinoic acid treatment: extended complete remission in an elderly AML patient with multi-hit TP53 lesions and complex-monosomal karyotype.

DNA-hypomethylating agents (HMAs) induce notable remission rates in AML/MDS patients with TP53 mutations; however, secondary resistance often develops rapidly. In the DECIDER trial (NCT00867672), elderly AML patients (also those with adverse genetics) randomized to all-trans retinoic acid (ATRA) added to decitabine (DEC) attained significantly delayed time-to-resistance. An 82-year-old patient with a non-disruptive, in-frame TP53 mutation (p.Cys238_Asn239delinsTyr, VAF 90%) and complex-monosomal karyotype attained a complete hematologic and cytogenetic remission with DEC + ATRA, with 3.7 years survival after 30 treatment cycles that were well-tolerated. Further HMA + ATRA studies appear warranted in AML/MDS patients of different genetic risk groups ineligible for more intensive treatment.Trial registration: This trial was registered at ClinicalTrials.gov identifier: NCT00867672.

Satellite DNAs and the evolution of the multiple X1X2Y sex chromosomes in the wolf fish Hoplias malabaricus (Teleostei; Characiformes).

Multiple sex chromosomes usually arise from chromosomal rearrangements which involve ancestral sex chromosomes. There is a fundamental condition to be met for their long-term fixation: the meiosis must function, leading to the stability of the emerged system, mainly concerning the segregation of the sex multivalent. Here, we sought to analyze the degree of differentiation and meiotic pairing properties in the selected fish multiple sex chromosome system present in the wolf-fish Hoplias malabaricus (HMA). This species complex encompasses seven known karyotype forms (karyomorphs) where the karyomorph C (HMA-C) exhibits a nascent XY sex chromosomes from which the multiple X1X2Y system evolved in karyomorph HMA-D via a Y-autosome fusion. We combined genomic and cytogenetic approaches to analyze the satellite DNA (satDNA) content in the genome of HMA-D karyomorph and to investigate its potential contribution to X1X2Y sex chromosome differentiation. We revealed 56 satDNA monomers of which the majority was AT-rich and with repeat units longer than 100 bp. Seven out of 18 satDNA families chosen for chromosomal mapping by fluorescence in situ hybridization (FISH) formed detectable accumulation in at least one of the three sex chromosomes (X1, X2 and neo-Y). Nine satDNA monomers showed only two hybridization signals limited to HMA-D autosomes, and the two remaining ones provided no visible FISH signals. Out of seven satDNAs located on the HMA-D sex chromosomes, five mapped also to XY chromosomes of HMA-C. We showed that after the autosome-Y fusion event, the neo-Y chromosome has not substantially accumulated or eliminated satDNA sequences except for minor changes in the centromere-proximal region. Finally, based on the obtained FISHpatterns, we speculate on the possible contribution of satDNA to sex trivalent pairing and segregation.

First insight into the genomes of the Pulmonaria officinalis group (Boraginaceae) provided by repeatome analysis and comparative karyotyping.

BACKGROUND: The genus Pulmonaria (Boraginaceae) represents a taxonomically complex group of species in which morphological similarity contrasts with striking karyological variation. The presence of different numbers of chromosomes in the diploid state suggests multiple hybridization/polyploidization events followed by chromosome rearrangements (dysploidy). Unfortunately, the phylogenetic relationships and evolution of the genome, have not yet been elucidated. Our study focused on the P. officinalis group, the most widespread species complex, which includes two morphologically similar species that differ in chromosome number, i.e. P. obscura (2n = 14) and P. officinalis (2n = 16). Ornamental cultivars, morphologically similar to P. officinalis (garden escapes), whose origin is unclear, were also studied. Here, we present a pilot study on genome size and repeatome dynamics of these closely related species in order to gain new information on their genome and chromosome structure. RESULTS: Flow cytometry confirmed a significant difference in genome size between P. obscura and P. officinalis, corresponding to the number of chromosomes. Genome-wide repeatome analysis performed on genome skimming data showed that retrotransposons were the most abundant repeat type, with a higher proportion of Ty3/Gypsy elements, mainly represented by the Tekay lineage. Comparative analysis revealed no species-specific retrotransposons or striking differences in their copy number between the species. A new set of chromosome-specific cytogenetic markers, represented by satellite DNAs, showed that the chromosome structure in P. officinalis was more variable compared to that of P. obscura. Comparative karyotyping supported the hybrid origin of putative hybrids with 2n = 15 collected from a mixed population of both species and outlined the origin of ornamental garden escapes, presumably derived from the P. officinalis complex. CONCLUSIONS: Large-scale genome size analysis and repeatome characterization of the two morphologically similar species of the P. officinalis group improved our knowledge of the genome dynamics and differences in the karyotype structure. A new set of chromosome-specific cytogenetic landmarks was identified and used to reveal the origin of putative hybrids and ornamental cultivars morphologically similar to P. officinalis.

Testicular mosaicism in non-mosaic postpubertal Klinefelter patients with focal spermatogenesis and in non-mosaic prepubertal Klinefelter boys.

STUDY QUESTION: Do testis-specific cells have a normal karyotype in non-mosaic postpubertal Klinefelter syndrome (KS) patients with focal spermatogenesis and in non-mosaic prepubertal KS boys? SUMMARY ANSWER: Spermatogonia have a 46, XY karyotype, and Sertoli cells surrounding these spermatogonia in postpubertal patients also have a 46, XY karyotype, whereas, in prepubertal KS boys, Sertoli cells surrounding the spermatogonia still have a 47, XXY karyotype. WHAT IS KNOWN ALREADY: A significant proportion of patients with non-mosaic KS can have children by using assisted reproductive techniques thanks to focal spermatogenesis. However, the karyotype of the cells that are able to support focal spermatogenesis has not been revealed. STUDY DESIGN, SIZE, DURATION: Testicular biopsy samples from non-mosaic KS patients were included in the study. Karyotyping for sex chromosomes in testis-specific cells was performed by immunohistochemical analysis of inactive X (Xi) chromosome and/or fluorescent in situ hybridization (FISH) analysis of chromosomes 18, X, and Y. PARTICIPANTS/MATERIALS, SETTING, METHODS: A total of 22 KS patients (17 postpubertal and 5 prepubertal) who were non-mosaic according to lymphocyte karyotype analysis, were included in the study. After tissue processing, paraffin embedding, and sectioning, the following primary antibodies were used for cell-specific analysis and Xi detection; one section was stained with MAGE A4 for spermatogonia, SOX9 for Sertoli cells, and H3K27me3 for Xi; the other one was stained with CYP17A1 for Leydig cells, ACTA2 for peritubular myoid cells, and H3K27me3 for Xi. Xi negative (Xi-) somatic cells (i.e. Sertoli cells, Leydig cells, and peritubular myoid cells) were evaluated as having the 46, XY karyotype; Xi positive (Xi+) somatic cells were evaluated as having the 47, XXY. FISH stain for chromosomes 18, X, and Y was performed on the same sections to investigate the karyotype of spermatogonia and to validate the immunohistochemistry results for somatic cells. MAIN RESULTS AND THE ROLE OF CHANCE: According to our data, all spermatogonia in both postpubertal and prepubertal non-mosaic KS patients seem to have 46, XY karyotype. However, while the Sertoli cells surrounding spermatogonia in postpubertal samples also had a 46, XY karyotype, the Sertoli cells surrounding spermatogonia in prepubertal samples had a 47, XXY karyotype. In addition, while the Sertoli cells in some of the Sertoli cell-only tubules had 46, XY karyotype, the Sertoli cells in some of the other Sertoli cell-only tubules had 47, XXY karyotype in postpubertal samples. In contrast to the postpubertal samples, Sertoli cells in all tubules in the prepubertal samples had the 47, XXY karyotype. Our data also suggest that germ cells lose the extra X chromosome during embryonic, fetal, or neonatal life, while Sertoli cells lose it around puberty. Peritubular myoid cells and Leydig cells may also be mosaic in both postpubertal patients and prepubertal boys, but it requires further investigation. LIMITATIONS, REASONS FOR CAUTION: The number of prepubertal testicle samples containing spermatogonia is limited, so more samples are needed for a definitive conclusion. The fact that not all the cell nuclei coincide with the section plane limits the accurate detection of X chromosomes by immunohistochemistry and FISH in some cells. To overcome this limitation, X chromosome analysis could be performed by different techniques on intact cells isolated from fresh tissue. Additionally, there is no evidence that X chromosome inactivation reoccurs after activation of the Xi during germ cell migration during embryogenesis, limiting the prediction of X chromosome content in germ cells by H3K27me3. WIDER IMPLICATIONS OF THE FINDINGS: Our findings will lay the groundwork for new clinically important studies on exactly when and by which mechanism an extra X chromosome is lost in spermatogonia and Sertoli cells. STUDY FUNDING/COMPETING INTEREST(S): This study was funded by The Scientific and Technological Research Council of Türkiye (TUBITAK) (2219 - International Postdoctoral Research Fellowship Program for Turkish Citizens) and the Strategic Research Program (SRP89) from the Vrije Universiteit Brussel. The authors declare no competing interests. TRIAL REGISTRATION NUMBER: N/A.

Karyotypic and phenotypic condensation in allotetraploid wheats accompanied with reproductive strategy transformation: from natural evolution to domestication.

MAIN CONCLUSION: Allotetraploid wheat reflects evolutionary divergence and domestication convergence in the karyotypic and phenotypic evolution, accompanied with the transformation from r- strategy to K- strategy in reproductive fitness. Allotetraploid wheat, the progenitor of hexaploidy bread wheat, has undergone 300,000 years of natural evolution and 10,000 years of domestication. The variations in karyotype and phenotype as well as fertility fitness have not been systematically linked. Here, by combining fluorescent in situ hybridization with the quantification of phenotypic and reproductive traits, we compared the karyotype, vegetative growth phenotype and reproductive fitness among synthesized, wild and domesticated accessions of allotetraploid wheat. We detected that the wild accessions showed dramatically high frequencies of homologous recombination and copy number variations of simple sequence repeats (SSR) comparing with synthetic and domesticated accessions. The phenotypic traits reflected significant differences among the populations shaped by distinct evolutionary processes. The diversity observed in wild accessions was significantly greater than that in domesticated ones, particularly in traits associated with vegetative growth and spike morphology. We found that the active pollen of domesticated accessions exhibited greater potential of germination, despite a lower rate of active pollen compared with the wild accessions, indicating a transformation in reproductive fitness strategy for pollen development in domesticated accessions compared to the wild accessions, from r-strategy to K-strategy. Our results demonstrate the condensation of karyotype and phenotype from natural wild accessions to domesticated accessions in allotetraploid wheats. Ecological strategy transformation should be seriously considered from evolution to domestication in polyploid plants, especially crops, which may provide a perspective on the adaptive evolution of polyploid plants.

The genomes of all lungfish inform on genome expansion and tetrapod evolution.

The genomes of living lungfishes can inform on the molecular-developmental basis of the Devonian sarcopterygian fish-tetrapod transition. We de novo sequenced the genomes of the African (Protopterus annectens) and South American lungfishes (Lepidosiren paradoxa). The Lepidosiren genome (about 91 Gb, roughly 30 times the human genome) is the largest animal genome sequenced so far and more than twice the size of the Australian (Neoceratodus forsteri)1 and African2 lungfishes owing to enlarged intergenic regions and introns with high repeat content (about 90%). All lungfish genomes continue to expand as some transposable elements (TEs) are still active today. In particular, Lepidosiren's genome grew extremely fast during the past 100 million years (Myr), adding the equivalent of one human genome every 10 Myr. This massive genome expansion seems to be related to a reduction of PIWI-interacting RNAs and C2H2 zinc-finger and Krüppel-associated box (KRAB)-domain protein genes that suppress TE expansions. Although TE abundance facilitates chromosomal rearrangements, lungfish chromosomes still conservatively reflect the ur-tetrapod karyotype. Neoceratodus' limb-like fins still resemble those of their extinct relatives and remained phenotypically static for about 100 Myr. We show that the secondary loss of limb-like appendages in the Lepidosiren-Protopterus ancestor was probably due to loss of sonic hedgehog limb-specific enhancers.

Comparative molecular and conventional cytogenetic analyses of three species of Rhinella (Anura; Bufonidae).

The genus Rhinella corresponds to a group of anurans characterized by numerous taxonomic and systemic challenges, leading to their organization into species complexes. Cytogenetic data for this genus thus far are limited to the diploid number and chromosome morphology, which remain highly conserved among the species. In this study, we analyse the karyotypes of three species of the genus Rhinella (Rhinella granulosa, Rhinella margaritifera, and Rhinella marina) using both classical (conventional staining and C-banding) and molecular (FISH-fluorescence in situ hybridization with 18S rDNA, telomeric sequences, and microsatellite probes) cytogenetic approaches. The aim of this study is to provide data that can reveal variations in the distribution of repetitive sequences that can contribute to understanding karyotypic diversification in these species. The results revealed a conserved karyotype across the species, with 2n = 22 and FN = 44, with metacentric and submetacentric chromosomes. C-banding revealed heterochromatic blocks in the pericentromeric region for all species, with a proximal block on the long arms of pairs 3 and 6 in R. marina and on the short arms of pairs 4 and 6 in R. margaritifera. Additionally, 18S rDNA probes hybridized to pair 5 in R. granulosa, to pair 7 in R. marina, and to pair 10 in R. margaritifera. Telomeric sequence probes displayed signals exclusively in the distal region of the chromosomes, while microsatellite DNA probes showed species-specific patterns. These findings indicate that despite a conserved karyotypical macrostructure, chromosomal differences exist among the species due to the accumulation of repetitive sequences. This variation may be attributed to chromosome rearrangements or differential accumulation of these sequences, highlighting the dynamic role of repetitive sequences in the chromosomal evolution of Rhinella species. Ultimately, this study emphasizes the importance of the role of repetitive DNAs in chromosomal rearrangements to elucidate the evolutionary mechanisms leading to independent diversification in the distinct phylogenetic groups of Rhinella.

Cytogenetic study of Meriz goat breeds in Iraqi Kurdistan region.

Goats are considered the leading farm animal that has a substantial role in the agricultural sector in the Kurdistan Region of Iraq. No cytological examination has been carried out on them. This experiment aims to identify the Karyotype of the local breeds of domestic goats. This experiment was conducted on the Karyotype and prepared the ideogram of Meriz goats. The determination of the relative length and centromeric index arm ratio of the chromosomes in the breed was achieved by the production of karyotypes. A total of (30)Meriz goats, consisting of (10) males and (20) females, were selected to collect blood samples for a short-term lymphocyte culture. The diploid chromosome count was observed to be (60), consisting of (29) pairs of acrocentric autosomes and one pair of allosomes, specifically the X and Y chromosomes. The acrocentric nature of the X-chromosome and the sub-metacentric nature of the Y-chromosome were identified through scientific investigation. The study observed a variation in the relative length of autosomal chromosomes in Meriz goats, with females ranging from 4.49% to 1.89% and males ranging from (4.53%) to (1.75%). The X-chromosome had a relative length of 3.96 in females, while the Y-chromosome displayed a relative length of (5.05). The findings of this karyological investigation suggest that the chromosomal composition seen in the Meriz goats under examination was within the expected range of normalcy. It is recommended that more cytogenetic analyses be conducted at the population level in order to identify individuals within the Meriz breed population who possesses numerical and/or structural chromosome abnormalities. This research is crucial for enhancing the efficiency of production and reproduction in this breed.

[Genetic analysis and PGT-SR outcome of a male carrier of exceptional complex chromosome rearrangement].

OBJECTIVE: To investigate the clinical and genetic characteristics of a male carrier of exceptional complex chromosome rearrangement (CCR) and the outcome of preimplantation genetic testing for chromosomal structural rearrangement (PGT-SR). METHODS: Using the modified high resolution G banding technique and whole-genome low-coverage sequencing (WGLCS), we analyzed the cellular karyotype and molecular karyotype of a male carrier of CCR, performed an analysis of the single-sperm chromosome copy number and conducted PGT-SR for the patient by next-generation sequencing (NGS). In addition, we reviewed the literature on reported male carriers of CCRs and summarized their normal/balanced sperm ratios and PGT-SR outcomes. RESULTS: The karyotype of the patient was 46,XY,der(5)inv(5)(q14.3q23.2)t(5;14;11) (q23.2;q31.1;q21),der(11)t(5;14;11);der(14)t(5;14;11), with the translocation breakpoints located in the intergenic region. Single-sperm sequencing revealed 20.0%（7/35）of normal haploids in the male's spermatozoa， and the results PGT-SR showed a proportion of 25.0%（4/16）of normal/balanced embryos. After thawing and transferring of 2 euploid blastocysts, a healthy male infant was successfully delivered. CONCLUSION: The proportion of normal haploids in the spermatozoa of male CCR carriers may be higher than theoretically predicted, and PGT-SR can effectively improve the pregnancy outcome in male CCR carriers and provide valuable data for genetic counseling.