Articles tagged with X Chromosomes
New research reveals that females with lupus have an abnormal expression of genes linked to their second X chromosome due to incomplete X inactivation in immune system T cells. This abnormality may contribute to the genetic missteps seen in lupus, and changes in nuclear structure may also play a role.
Researchers at Karolinska Institutet discovered previously unknown cellular stages of fetal development using gene analysis on individual cells from early mouse embryos. The study revealed a molecular road-map of the events that control cell differentiation, shedding new light on the early development of the embryo.
Researchers have discovered that RNA splicing plays a crucial role in the X chromosome inactivation process in females. This mechanism, involving the Xist gene, determines females' susceptibility to diseases such as Fragile X and Rett syndromes.
Researchers from UNIGE analyzed skin and blood cells from five women, identifying 55 genes that escape inactivation of the second X chromosome. The team found that XIST gene expression is key to inactivation, but also discovered five other genes playing a crucial role in the mechanism.
Researchers at UC San Francisco have found that female mice live longer than males due to the presence of two X chromosomes. Having both female sex chromosomes and gonads extended life in mice, with most of the effect coming from the sex chromosomes.
Researchers created a female mouse model with limited MECP2 gene expression, extending lifespan and reducing symptoms. The study suggests that partial reactivation of the inactive X chromosome may be therapeutic for Rett syndrome.
A study on Rett syndrome found that small molecule inhibitors reactivated the inactive X-linked MECP2 gene, rectifying morphological defects in human induced pluripotent stem cell-derived neurons. The treatment has potential therapeutic applications for the neurodevelopmental disorder.
Researchers at Massachusetts General Hospital identify SMCHD1 as critical regulator of X chromosome inactivation, allowing genes to be suppressed. The study's findings have implications for treating diseases associated with misfolded chromatin and hold promise for reactivating the inactive X chromosome.
Male and female cells behave differently after being reprogrammed into stem cells due to their number of X chromosomes. This affects DNA methylation, a process that changes DNA activity without changing its sequence.
A new mutation on the X-chromosome has been identified as a potential contributor to earlier onset ovarian cancer in women. The study also found an association between this mutation and higher rates of prostate cancer in fathers and sons.
Researchers at Linköping University found that fruit flies do not have a shorter lifespan due to having one X chromosome. Instead, the study suggests that competition for mates may be responsible for the sex difference in lifespan. Further research will investigate alternative theories.
A recent study at the University of Turku found that X-chromosome relatedness between grandmothers and their grandchildren did not affect grandchild survival. The study tested a hypothesis about the genetic inheritance of grandmothers' help towards their grandchildren, but did not produce enough support for its claims.
A Massachusetts General Hospital team developed a dual-modality approach to reactivate the inactive X chromosome, increasing MECP2 protein expression up to 30,000-fold. The treatment may provide meaningful treatment for patients with Rett syndrome and other X-linked disorders.
Researchers at the University of Pennsylvania discovered a dynamic two-step mechanism in female immune cells to regulate X chromosome inactivation. B cells regain X-chromosome markers during activation through the transcription factor YY1, leading to increased gene expression related to immunity.
A comprehensive analysis of gene variants in 23 different tissues and developmental stages of mice reveals tissue-specific differences in gene variant activity. The study found that genetic and epigenetic differences contribute to these patterns, with some genes escaping X-chromosome inactivation and exhibiting high rates of activity.
Researchers found a region on chromosome 19 that represses Xist, allowing for the activation of multiple X chromosomes in female embryos. This discovery may explain the worldwide human sex ratio, which has slightly favored males over females.
A team of researchers solved a medical mystery in just one day, identifying the genetic cause of intellectual disability in four male patients. They used advanced technology to search genomic databases and connect with other researchers, ultimately finding three more patients with the same condition.
Scientists have discovered a new long RNA molecule, XACT, which accumulates with XIST on active X-chromosomes in human embryos. This finding explains why XIST is unable to trigger X-chromosome silencing until later stages of development. The research also reveals that XACT restrains XIST activity before chromosome silencing occurs.
Research at McGill University has identified a link between decreased X chromosome gene PPP2R3B expression and tumor progression in melanoma. The findings suggest that genetic specificity of the X chromosome plays a role in gender differences observed in melanoma prognosis.
A study published in Nature Genetics found that certain genetic mutations more frequently occur in male cells, potentially leading to cancer. The researchers identified six genes on the X chromosome that are more likely to be mutated in males, suggesting a new theory behind the sex disparity in cancer incidence.
A breakthrough study published in Nature reveals that the fine detail of DNA shape plays a crucial role in distinguishing X chromosome binding sites from other chromosomes. The researchers identified a specific sequence signature called PionX, which is selectively recognized by the dosage compensation complex, enabling gene regulation.
Researchers developed a detailed model system to study the Barr body's highly organized structure, revealing two distinct lobes with smaller active DNA domains. Topologically associating domains play a significant role in gene expression within the otherwise inactive lobes.
Researchers discover DXZ4 repeats play a crucial role in superloop formation on the inactive X chromosome. The discovery sheds light on female development and has implications for 3D genome engineering.
Researchers reveal that unusual DNA repeat elements on inactive X chromosomes are crucial for maintaining the three-dimensional structure of this female-specific genetic phenomenon. The study uses genome engineering techniques to demonstrate the importance of these repeats, opening a new era of genomics research.
A new study reveals that a simple GAGA DNA sequence is essential for dosage compensation in insects, allowing males to achieve double gene expression on their X chromosome. This process likely evolved independently among different species and may be applicable to other animals, including mammals.
A study published in PLOS Biology shows that multiple mechanisms regulate expression of genes from the single X chromosome in Drosophila testes, reflecting a balance between chromosome-wide transcriptional suppression and compensatory evolution by sex-linked genes. This balance has consequences for gene expression and genome evolution.
Stanley M. Gartler, PhD, receives the 2016 Victor A. McKusick Leadership Award for his extensive research in X chromosome inactivation, somatic cells, and tumor biology. He has made significant discoveries and connections across multiple fields.
Researchers at Arizona State University have found that X and Y DNA swapping may occur much more frequently than previously believed. This promiscuous swapping could lead to a better understanding of human history, diversity, health, and disease, as well as blur rigid chromosomal interpretations of sexual identity.
Researchers discovered that female lymphocytes lack proper X chromosome inactivation, leading to increased expression of immunity-related genes. This incomplete activation may contribute to autoimmune conditions like lupus, which affects 85% of female patients.
Researchers replaced the Y chromosome in mice by increasing expression of two genes, Sry and Eif2s3y, allowing males to produce offspring. The study demonstrates the mammalian genome's plasticity by exchanging Y chromosome genes with those on other chromosomes.
A team of researchers led by Professor Laurence Hurst found that the X chromosome contains few 'housekeeping' genes due to a single active copy, limiting its expression. The study identified gene migration patterns between chromosomes and suggests that replacement genes should not be inserted into the X chromosome for gene therapy.
Scientists discover that Xist RNA is insufficient to silence one of the two X chromosomes in every female cell, suggesting a complex interplay between molecules. This finding could lead to new ways to fight X-linked diseases in females, including those linked to autism, hemophilia, and muscular dystrophy.
A team of scientists from the University of Michigan Medical School has discovered a new way for RNA to regulate genetic activity on the X chromosome in females. The finding, which could lead to better treatment for sex-linked disorders, shows that female cells produce a special type of RNA called XistAR to silence one of their two X c...
A team of ETH Zurich researchers has identified seven genes central to X chromosome inactivation in females, including Spen, which prevents gene expression at the X chromosome. The discovery sheds light on how the human body maintains a delicate balance between genes, preventing disease.
New research reveals mutations in the X chromosome gene TEX11 are linked to 1% of azoospermia cases, a condition where men produce no sperm. The study found that reintroducing the gene restores fertility in mice, highlighting the protein's role in sperm formation and chromosomal arrangements.
A team led by Professor Jozef Gecz has identified a gene mutation responsible for female-only epilepsy and found a treatment using synthetic allopregnanolone, promising to delay seizure onset and reduce autism and intellectual disability effects.
Researchers at University of California, San Diego School of Medicine have identified a biological marker for mental illness in female patients. The study found that specific genes, including XIST, are over-produced in women with mental illnesses like bipolar disorder, major depression, and schizophrenia.
Researchers found four essential genes that were lost from the human Y chromosome but relocated to other chromosomes, including one gene crucial for sperm production. These findings suggest a complex role of sex chromosomes in genetic function and may contribute to male infertility.
Researchers at Caltech have discovered the detailed mechanism of action for Xist, an lncRNA that silences the X chromosome in female embryos. By understanding how Xist works, scientists can gain insights into long non-coding RNAs and their role in regulating cellular processes.
Researchers have discovered seven new genes associated with X-linked intellectual disability, a condition that affects mostly men. The study used genetic analysis to identify mutations on the X chromosome as the cause of the disorder, which has highly variable clinical manifestations.
TGen researchers developed a new test that leverages the unique genetic difference between men and women to track down neurological disorders in young girls. By analyzing DNA sequences, they were able to identify a previously unrecognized disorder in a pre-teen girl and provide more accurate diagnosis for families.
Researchers Beatriz Vicoso and Doris Bachtrog found that genes on the 'dot chromosome' of fruit flies are X-linked in three other species, suggesting a history as a sex chromosome. They identified nine independently evolved sex chromosomes with balanced gene expression between males and females.
Researchers from Penn and CHOP confirmed a genetic link between missing DNA on the X chromosome and birth defects such as epilepsy, cleft palate, and respiratory failure. The study provides a mouse model to investigate the underlying molecular mechanism of these conditions and potentially identify genes responsible.
Scientists have visualized the inactive X chromosome in intact cells for the first time, revealing its unique substructural organization. This breakthrough could help understand gene activity and inheritance patterns, with potential implications for diagnosing and treating X-chromosome-linked diseases.
Researchers analyzed genetic variation in the X chromosome to understand individual differences in traits such as height, BMI, and blood pressure. They identified a genetic variant near ITM2A that affects cartilage development and is more prevalent among shorter individuals, with stronger effects on women.
Scientists have developed a new technique to visualize the silencing of one X chromosome in females, revealing wide-ranging variation in patterns across tissues and individuals. The study's findings offer insights into genetic diversity and disease causes, particularly for X-linked variations like hemophilia and color blindness.
Scientists have successfully silenced extra chromosome 21 in laboratory cultures of patient-derived stem cells using a gene-silencing strategy. This approach reveals genome-wide changes and offers hope for identifying cellular pathways deregulated in Down syndrome, paving the way for potential therapeutics.
Researchers found hypermutation of inactive X chromosome is a common event in cancer, especially in rapidly growing tumors. This phenomenon affects only the inactive copy of the X chromosome and contributes to carcinogenesis.
A study has identified 114 genes on the X chromosome that have escaped silencing, including 76 previously unknown. These genes are often associated with mental impairment and may hold clues to better management of XXX syndrome.
Researchers found a new switch involved in dosage compensation, which doubles gene activity on the male X chromosome. This switch, revealed to be a hairpin structure, must be unwound by an enzyme before MSL proteins can bind, allowing for functional assembly of the Dosage Compensation Complex.
Scientists from Max Planck Institute of Immunobiology and Epigenetics found that the protein MLE molds the RNA strand, allowing it to bind with other proteins. This dynamic interaction enables the entire X chromosome to be covered by the RNA-protein complex, essential for sex chromosome activation.
A groundbreaking study reveals that nearly 340 genes on the X chromosome contribute to sperm production, surprising scientists who once viewed it as a stable and unchanging chromosome. The research, published in Nature Genetics, uses advanced sequencing methods to assemble the first accurate reference sequence of the human X chromosome.
The newly found CLAMP protein plays a crucial role in regulating the X chromosome in male fruit flies, enabling them to develop and survive. By working together with the MSL complex, CLAMP creates a self-reinforcing feedback loop that enhances gene expression, providing a model for understanding how proteins govern gene transcription.
Researchers establish proof-of-principal for silencing extra chromosome 21 in cells, advancing translational research and surmounting major obstacle to 'chromosome therapy'. This breakthrough paves the way for studying cell pathologies and identifying genome-wide pathways implicated in Down syndrome.
Researchers discovered how lncRNAs use positional information to locate and bind to nearby genes, forming a compartment where multiple genes can be regulated together. This unique mechanism allows lncRNAs to organize key proteins involved in gene expression.
Researchers have discovered a new therapy for fragile X chromosome syndrome by modulating the cerebral endocannabinoid system. The treatment has shown promise in normalizing cognitive alterations and sensitivity to pain in genetically modified mice, suggesting a potential new strategy for treating patients with FXS.
A new study published in PLOS Genetics found that brown bears on Alaskan archipelago descended from polar bears through hybridization, not the other way around. The research used DNA sequencing to analyze the X chromosomes of the brown bears and found that 6.5% of them had recently come from polar bears.
A study by Jana Beckelmann found that female horse embryos produce more insulin-like growth factor-1 (IGF1) than male embryos, which may help explain the uneven sex ratio of equine births. This discovery sheds light on a previously unknown mechanism driving sexual dimorphism in horses.
Researchers have broadened the understanding of how cells regulate silencing of the X chromosome, finding indications of gene activity inside and outside the Xist cloud. The study's findings suggest a more subtle regulation mechanism than previously thought, with potential implications for cancer therapy and non-coding RNA function.
Researchers identified a genetic variant on chromosome X that predicts high-risk men who drink heavily are at risk for developing chronic pancreatitis. The discovery enables doctors to identify patients with early signs of pancreatitis or acute attacks, allowing them to take preventative action and give the pancreas a chance to heal.