Male homosexuality is a complex phenomenon which is universal and with unknown causes. Researchers believe that both biological and environmental factors have played a role in its pathogenesis. Researches focusing on genetics, neurobiology, development and endocrinology have made certain progress. In this paper, we have reviewed the biological causes of male homosexuality, which may provide clues for further research in this field.
Developmental Biology ; Endocrinology ; Homosexuality, Male ; Humans ; Male ; Neurobiology

Forensic entomology provides a feasible way to estimate postmortem interval (PMI), of which the growth and development of sarcosaprophagous insects is the most widely used indicator in forensic practice. Over the years, forensic entomologists have carried out a large number of studies on the development biology of sarcosaprophagous insects. This paper illustrates the main factors that affect the development of sarcosaprophagous insects, including temperature, humidity, light, food types and poisons. The development indicators of sarcosaprophagous insects were reviewed from the perspectives of morphology, differential gene expression and biochemical characteristics. It is emphasized that future research of development biology on sarcosaprophagous insects should fully absorb and integrate the methods of artificial intelligence and omics, and the research object also needs further expansion in order to establish a more objective and more accurate PMI estimation method.
Animals ; Artificial Intelligence ; Developmental Biology ; Diptera ; Entomology ; Insecta ; Postmortem Changes

OBJECTIVETo examine the important roles of microRNAs (miRNAs) in regulating amphid structure and function, we performed a computational analysis for the genetic loci required for the sensory perception and their possibly corresponding miRNAs in C. elegans.

METHODSTotal 55 genetic loci required for the amphid structure and function were selected. Sequence alignment was combined with E value evaluation to investigate and identify the possible corresponding miRNAs.

RESULTSTotal 30 genes among the 55 genetic loci selected have their possible corresponding regulatory miRNA (s), and identified genes participate in the regulation of almost all aspects of amphid structure and function. In addition, our data suggest that both the amphid structure and the amphid functions might be regulated by a series of network signaling pathways. Moreover, the distribution of miRNAs along the 3' untranslated region (UTR) of these 30 genes exhibits different patterns.

CONCLUSIONWe present the possible miRNA-mediated signaling pathways involved in the regulation of chemosensation and thermosensation by controlling the corresponding sensory neuron and interneuron functions. Our work will be useful for better understanding of the miRNA-mediated control of the chemotaxis and thermotaxis in C. elegans.

Animals ; Caenorhabditis elegans ; embryology ; genetics ; Caenorhabditis elegans Proteins ; biosynthesis ; genetics ; Cilia ; genetics ; Computational Biology ; methods ; Gene Expression Regulation, Developmental ; genetics ; Genome ; genetics ; MicroRNAs ; genetics ; Models, Genetic ; Nervous System ; embryology ; metabolism ; Neurons, Afferent ; metabolism ; Sensation ; genetics ; Signal Transduction ; genetics

Understanding limb development not only gives insights into the outgrowth and differentiation of the limb, but also has clinical relevance. Limb development begins with two paired limb buds (forelimb and hindlimb buds), which are initially undifferentiated mesenchymal cells tipped with a thickening of the ectoderm, termed the apical ectodermal ridge (AER). As a transitional embryonic structure, the AER undergoes four stages and contributes to multiple axes of limb development through the coordination of signalling centres, feedback loops, and other cell activities by secretory signalling and the activation of gene expression. Within the scope of proximodistal patterning, it is understood that while fibroblast growth factors (FGFs) function sequentially over time as primary components of the AER signalling process, there is still no consensus on models that would explain proximodistal patterning itself. In anteroposterior patterning, the AER has a dual-direction regulation by which it promotes the sonic hedgehog (Shh) gene expression in the zone of polarizing activity (ZPA) for proliferation, and inhibits Shh expression in the anterior mesenchyme. In dorsoventral patterning, the AER activates Engrailed-1 (En1) expression, and thus represses Wnt family member 7a (Wnt7a) expression in the ventral ectoderm by the expression of Fgfs, Sp6/8, and bone morphogenetic protein (Bmp) genes. The AER also plays a vital role in shaping the individual digits, since levels of Fgf4/8 and Bmps expressed in the AER affect digit patterning by controlling apoptosis. In summary, the knowledge of crosstalk within AER among the three main axes is essential to understand limb growth and pattern formation, as the development of its areas proceeds simultaneously.
Animals ; Apoptosis ; Body Patterning ; Bone Morphogenetic Proteins/biosynthesis* ; Developmental Biology ; Ectoderm/metabolism* ; Extremities/embryology* ; Fibroblast Growth Factor 10/metabolism* ; Fibroblast Growth Factors/biosynthesis* ; Gene Expression Regulation ; Hedgehog Proteins/biosynthesis* ; Homeodomain Proteins/biosynthesis* ; Mesoderm/metabolism* ; Mice ; Signal Transduction ; Wnt Proteins/biosynthesis*

Many advances have been made in understanding the molecular biology of brain tumors through progress in cell and developmental biology. The molecular characterization of rare genetic disorders and tumors shed light on several common tumorigenic mechanisms: mitogenic signaling, cell cycle control, development, and cell surface-cytoskeleton interactions. Discovery of many new molecular markers and the recent identification of brain tumor stem cells offer new directions in future research for tumor molecular diagnostics and therapies.
Brain Neoplasms* ; Brain* ; Cell Cycle Checkpoints ; Developmental Biology ; Glioma ; Medulloblastoma ; Meningioma ; Molecular Biology* ; Pathology, Molecular ; Stem Cells

OBJECTIVETo investigate the expression characteristics of the gene of coiled-coil domain-containing protein 70 (Ccdc70) in the mouse testis and its potential role in spermatogenesis.

METHODSUsing expression profile microarray, we screened the mouse testis-specific gene Ccdc70, studied its expression characteristics in the mouse testis by RT-PCR, real-time PCR, Western blot and immunohistochemistry, followed by bioinformatic analysis of the Ccdc70 protein.

RESULTSThe Ccdc70 gene was expressed highly in the testis but lowly in the epididymis of the mice. The Ccdc70 protein was expressed mainly in the spermatocytes and round spermatids of the testis and in the epithelial cells of the epididymis. Bioinformatic analysis showed a structural domain in the Ccdc70 protein, which was highly conserved in mammalian evolution.

CONCLUSIONThe Ccdc70 gene is highly expressed in the mouse testis and mainly in the spermatocytes, round spermatids, and epididymal epithelial cells, which indicates that it is involved in the regulation of spermatogenesis and epididymal sperm maturation.

Animals ; Computational Biology ; Gene Expression Regulation, Developmental ; Male ; Mice ; Proteins ; genetics ; Spermatogenesis ; genetics ; Testis ; metabolism

OBJECTIVE: To explore the genetic basis for a child featuring global developmental disorder with epilepsy. METHODS: A child who had presented at Guangzhou Women and Children's Medical Center in July 2022 was selected as the study subject. Clinical data was collected. Potential variant was detected by whole exome sequencing (WES). Candidate variant was validated by Sanger sequencing and bioinformatic analysis. RESULTS: The child, a three-year-old ethnic Zhuang Chinese girl, had presented with global developmental disorder and epilepsy, for which rehabilitation therapy was ineffective. Genetic testing revealed that she has harbored a homozygous c.821T>C (p.Leu274Pro) missense variant of the PIGW gene, for which both of her parents and sister were heterozygous carriers. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), the variant was classified as variant of uncertain significance. CONCLUSION The homozygous c.821T>C (p.Leu274Pro) variant of the PIGW gene probably underlay the onset of disease in this child. Above finding has enriched the mutational spectrum of the PIGW gene.
Child, Preschool ; Female ; Humans ; Computational Biology ; Developmental Disabilities ; Epilepsy/genetics* ; Genetic Testing ; Homozygote

Variation in human skin and hair color is the most notable aspect of human variability and several studies in evolution, genetics and developmental biology contributed to explain the mechanisms underlying human skin pigmentation, which is responsible for differences in skin color across the world's populations. Despite skin pigmentation is primarily related to melanocytes functionality, the surrounding keratinocytes and extracellular matrix proteins and fibroblasts in the underlying dermal compartment actively contribute to cutaneous homeostasis. Many autocrine/paracrine secreted factors and cell adhesion mechanisms involving both epidermal and dermal constituents determine constitutive skin pigmentation and, whenever deregulated, the occurrence of pigmentary disorders. In particular, an increased expression of such mediators and their specific receptors frequently lead to hyperpigmentary conditions, such as in melasma and in solar lentigo, whereas a defect in their expression/release is related to hypopigmented disorders, as seen in vitiligo. All these interactions underline the relevant role of pigmentation on human evolution and biology.
Biology ; Cell Adhesion ; Developmental Biology ; Extracellular Matrix Proteins ; Fibroblasts ; Genetics ; Hair Color ; Homeostasis ; Humans ; Intercellular Signaling Peptides and Proteins ; Keratinocytes ; Lentigo ; Melanocytes ; Melanosis ; Pigmentation ; Skin Pigmentation* ; Skin* ; Vitiligo

Knowledge of developmental biology is essential for clinicians who seek to develop a rational approach to the diagnostic evaluation of patients with birth defects. After an accurate diagnosis, a clinician can make predictions about prognosis, recommend management options, and provide an indication of recurrence risk for the parents and relatives. In this paper, we first review the basic mechanisms of embryological development and clinical dysmorphology. We then review cellular and molecular mechanisms in development and related congenital anomalies. Developmental anomalies have a major impact on public health. Genetic counseling and prenatal diagnosis, with the option to continue or to terminate a pregnancy, are important for helping families faced with the risk of a serious congenital anomaly in their offspring. Moreover, primary prevention of birth defects, for example, supplementation of prenatal folic acid and prevention of consumption of alcohol which has teratogenic effects, can be accomplished using developmental biology knowledge.
Congenital Abnormalities ; Developmental Biology ; Folic Acid ; Genetic Counseling ; Humans ; Parents ; Parturition ; Pregnancy ; Prenatal Diagnosis ; Primary Prevention ; Prognosis ; Public Health ; Recurrence

Stem cells are the body's master cells and have the ability to produce all manner of tissues. Embryonic stem(ES) cells, derived from the inner cell mass(ICM) of the mammalian blastocyst, can continuously proliferate in an undifferentiated state and differentiate into a desired cell lineage under certain conditions. These abilities make ES cells an appealing source for cell replacement therapies, the study of developmental biology, and drug/ toxin screening studies. Compared to mouse ES cells, human ES cells have only recently been derived and studied. Although there are many differences in properties between mouse and human ES cells, the study of mouse ES cells has provided important insight into human ES cell research. In this review, I describe the advantages and disadvantages of methods used for human ES cell derivation, the expansion of human ES cells.
Animals ; Blastocyst ; Cell Lineage ; Chromosome Aberrations ; Developmental Biology ; Embryonic Stem Cells* ; Humans* ; Mass Screening ; Mice ; Stem Cells