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Topic Review
10q26 Deletion Syndrome
10q26 deletion syndrome is a condition that results from the loss (deletion) of a small piece of chromosome 10 in each cell. The deletion occurs on the long (q) arm of the chromosome at a position designated 10q26.
  • 2.6K
  • 26 Aug 2021
Topic Review
SOX2 Anophthalmia Syndrome
SOX2 anophthalmia syndrome is a rare disorder characterized by abnormal development of the eyes and other parts of the body.
  • 2.4K
  • 24 Dec 2020
Topic Review
Swyer Syndrome
Swyer syndrome is a condition that affects sexual development. Sexual development is usually determined by an individual's chromosomes; however, in Swyer syndrome, sexual development does not match the affected individual's chromosomal makeup.  
  • 2.4K
  • 23 Dec 2020
Topic Review
Cline
In biology, a cline (from the Greek κλίνειν klinein, meaning "to lean") is a measurable gradient in a single character (or biological trait) of a species across its geographical range. First coined by Julian Huxley in 1938, the "character" of the cline referred to is usually genetic (e.g. allele frequency, blood type), or phenotypic (e.g. body size, skin pigmentation). Clines can show smooth, continuous gradation in a character, or they may show more abrupt changes in the trait from one geographic region to the next. A cline refers to a spatial gradient in a specific, singular trait, rather than a collection of traits; a single population can therefore have as many clines as it has traits, at least in principle. Additionally, Huxley recognised that these multiple independent clines may not act in concordance with each other. For example, it has been observed that in Australia, birds generally become smaller the further towards the north of the country they are found. In contrast, the intensity of their plumage colouration follows a different geographical trajectory, being most vibrant where humidity is highest and becoming less vibrant further into the arid centre of the country. Because of this, clines were defined by Huxley as being an "auxiliary taxonomic principle"; that is, clinal variation in a species is not awarded taxonomic recognition in the way subspecies or species are. While the terms "ecotype" and "cline" are sometimes used interchangeably, they do in fact differ in that "ecotype" refers to a population which differs from other populations in a number of characters, rather than the single character that varies amongst populations in a cline.
  • 2.4K
  • 09 Nov 2022
Topic Review
LncRNA Mechanisms of Action
Long non-coding (lnc)RNAs have emerged as critical regulators of gene expression and are involved in almost every cellular process. They can bind to other molecules including DNA, proteins, or even other RNA types such messenger RNA or small RNAs. LncRNAs are typically expressed at much lower levels than mRNA, and their expression is often restricted to tissue- or time-specific developmental stages. They are also involved in several inter-species interactions, including vector–host–pathogen interactions, where they can be either vector/host-derived or encoded by pathogens. In these interactions, they function via multiple mechanisms including regulating pathogen growth and replication or via cell-autonomous antimicrobial defense mechanisms. Recent advances suggest that characterizing lncRNAs and their targets in different species may hold the key to understanding the role of this class of non-coding RNA in interspecies crosstalk. 
  • 2.4K
  • 07 Feb 2021
Topic Review
Mabry Syndrome
Mabry syndrome is a condition characterized by intellectual disability, distinctive facial features, increased levels of an enzyme called alkaline phosphatase in the blood (hyperphosphatasia), and other signs and symptoms.
  • 2.2K
  • 23 Dec 2020
Topic Review
How Genes Work
Most genes contain the information needed to make functional molecules called proteins. Proteins do most of the work in cells and are required for the structure, function, and regulation of the body's tissues and organs.
  • 2.1K
  • 24 Dec 2020
Topic Review
Depression
Depression (also known as major depression or major depressive disorder) is a psychiatric disorder that affects mood, behavior, and overall health. It causes prolonged feelings of sadness, emptiness, or hopelessness, and a loss of interest in activities that were once enjoyed. People with depression may also have changes in appetite (leading to overeating or not eating enough), changes in sleeping patterns (sleeping too much or not being able to sleep), loss of energy, and difficulty concentrating. Although depression is considered primarily a mental health disorder, it can also have physical features including headaches, other unexplained aches and pains, unusually slow or fast movements, and digestive problems. To be diagnosed with depression, an individual must have signs and symptoms nearly every day for at least 2 weeks. However, the features of this condition vary widely.
  • 2.0K
  • 31 Dec 2020
Topic Review
Cloned Goats
The Cloned Goats or Transgenic Cloned Goats are generated and/or multiplied by one the most advanced and widely applied assisted reproductive technologies (ARTs) designated as somatic cell cloning or somatic cell nuclear transfer (SCNT). The SCNT-derived goats can provide a valuable tool for a variety of transgenic, biomedical, biopharmaceutical and nutri-biotechnological research.
  • 2.0K
  • 21 Jul 2021
Topic Review
TNF
TNF is a gene that plays an essential role in the body, it affects both immune response and inflammation. The gene encodes a protein called tumour necrosis factor alpha (TNFα) [1].
  • 2.0K
  • 05 Nov 2020
Topic Review
Mitogen-Activated Protein Kinase Signaling Pathway
The basic composition of the mitogen-activated protein kinase (MAPK) pathway is divided into three modules in sequence, with a cascade effect: MAPK kinase kinase (MAPKKK), MAPK kinase (MAPKK), and MAPK. The MAPK signaling pathway is activated in over 50% of human oral cancer cases.
  • 2.0K
  • 11 Oct 2022
Topic Review
Cladistics
Cladistics (/kləˈdɪstɪks/; from grc κλάδος (kládos) 'branch') is an approach to biological classification in which organisms are categorized in groups ("clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics (synapomorphies) that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms worms or fishes were used within a strict cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. Radiation results in the generation of new subclades by bifurcation, but in practice sexual hybridization may blur very closely related groupings. As a hypothesis, a clade can only be rejected if some groupings were explicitly excluded. It may then be found that the excluded group did actually descend from the last common ancestor of the group, and thus emerged within the group. ("Evolved from" is misleading, because in cladistics all descendants stay in the ancestral group). Upon finding that the group is paraphyletic this way, either such excluded groups should be granted to the clade, or the group should be abolished. Testifying to human focus, bias and perhaps exceptionalism, humans have never been placed in a paraphyletic group, whereas most other organisms have been. Branches down to the divergence to the next significant (e.g. extant) sister are considered stem-groupings of the clade, but in principle each level stands on its own, to be assigned a unique name. For a fully bifurcated tree, adding a group to a tree also adds an additional (named) clade, and potentially a new level. Specifically, also extinct groups are always put on a side-branch, not distinguishing whether an actual ancestor of other groupings was found. The techniques and nomenclature of cladistics have been applied to disciplines other than biology. (See phylogenetic nomenclature.) Cladistics findings are posing a difficulty for taxonomy, where the rank and (genus-)naming of established groupings may turn out to be inconsistent. Cladistics is now the most commonly used method to classify organisms.
  • 1.9K
  • 19 Oct 2022
Topic Review
Disorders of Sex Development
Disorders of sex development (DSDs), also known as differences in sex development, diverse sex development and variations in sex characteristics (VSC), are medical conditions involving the reproductive system. More specifically, these terms refer to "congenital conditions in which development of chromosomal, gonadal, or anatomical sex is atypical." The term has been controversial, and research has shown that affected people experience a negative impact, with the terminology impacting choice and utilization of health care providers. The World Health Organization and many medical journals still reference DSDs as intersex traits or conditions. The Council of Europe and Inter-American Commission on Human Rights have called for a review of medical classifications that unnecessarily medicalize intersex traits.
  • 1.9K
  • 09 Oct 2022
Topic Review
GADD45A
The growth arrest and DNA damage-inducible 45 alpha (GADD45A) gene encodes a 165 aa protein localized in the nucleus, whose level is highest in the G1 phase of the cell cycle, with a substantial reduction in S. The involvement of GADD45A in the cell cycle regulation and interaction with other proteins underline its function in the cellular DNA damage response and maintaining genomic stability, which, in turn, determines its high potential in cancer transformation. The protective role of GADD45A in DNA damage-induced tumorigenesis is the main biological function of this protein, but exact mechanism of it is not known. Emerging evidence suggests that GADD45A may be important in breast cancer and several molecular pathways were reported to underline this importance, including Ras, mitogen-activated protein kinase 8 (MAPK8), JNK (c-Jun N-terminal kinase) and p38. GADD45A may play a tumor-suppressor role by induction of senescence and apoptosis in cancer cells. However, it was also shown that GADD45A may promote tumorigenesis via the GSK3 β (glycogen synthase kinase 3 beta)/β-catenin signaling. Therefore, GADD45A may function as either a tumor promotor or suppressor, depending on the kind of oncogenic stress, and these two functions are mediated by different signaling pathways.
  • 1.8K
  • 01 Nov 2020
Topic Review
3D Genome
The genome is the most functional part of a cell, and genomic contents are organized in a compact three-dimensional (3D) structure. The genome contains millions of nucleotide bases organized in its proper frame. Rapid development in genome sequencing and advanced microscopy techniques have enabled us to understand the 3D spatial organization of the genome. Chromosome capture methods using a ligation approach and the visualization tool of a 3D genome browser have facilitated detailed exploration of the genome. 
  • 1.8K
  • 04 Nov 2021
Topic Review
Sonic Hedgehog
Sonic hedgehog is a protein encoded for by the SHH gene. The protein is named after the character Sonic the Hedgehog. This signaling molecule is key in regulating embryonic morphogenesis in all different types of animals. SHH controls organogenesis and the organization of the central nervous system, limbs, digits and many other parts of the body. Sonic hedgehog is a morphogen that patterns the developing embryo using a concentration gradient characterized by the French Flag model. This model has a non-uniform distribution of SHH molecules which governs different cell fates according to concentration. Mutations in this gene can cause holoprosencephaly, a failure of splitting in the cerebral hemispheres, as demonstrated in an experiment using SHH knock-out mice in which the forebrain midline failed to develop and instead only a single fused telencephalic vesicle resulted. Sonic hedgehog still plays a role in differentiation, proliferation, and maintenance of adult tissues. Abnormal activation of SHH signaling in adult tissues has been implicated in various types of cancers including breast, skin, brain, liver, gallbladder and many more.
  • 1.8K
  • 21 Nov 2022
Topic Review
Breast Cancer Pathology and Biomarkers
This contribution describes breast pathology and breast cancer incidence and mortality statistics. The contribution also discusses the clinical performance of already approved breast cancer biomarkers and their performance is compared to novel discovered breast cancer biomarkers.
  • 1.8K
  • 28 Jul 2020
Topic Review
Testis-Determining Factor
An Error has occurred retrieving Wikidata item for infobox Testis-determining factor (TDF), also known as sex-determining region Y (SRY) protein, is a DNA-binding protein (also known as gene-regulatory protein/transcription factor) encoded by the SRY gene that is responsible for the initiation of male sex determination in therian mammals (placental mammals and marsupials). SRY is an intronless sex-determining gene on the Y chromosome. Mutations in this gene lead to a range of disorders of sex development (DSD) with varying effects on an individual's phenotype and genotype. TDF is a member of the SOX (SRY-like box) gene family of DNA-binding proteins. When complexed with the SF1 protein, TDF acts as a transcription factor that causes upregulation of other transcription factors, most importantly SOX9. Its expression causes the development of primary sex cords, which later develop into seminiferous tubules. These cords form in the central part of the yet-undifferentiated gonad, turning it into a testis. The now-induced Leydig cells of the testis then start secreting testosterone, while the Sertoli cells produce anti-Müllerian hormone. SRY gene effects normally take place 6–8 weeks after fetus formation which inhibits the female anatomical structural growth in males. It also works towards developing the dominant male characteristics.
  • 1.7K
  • 25 Oct 2022
Topic Review
MED13L Syndrome
MED13L syndrome is a developmental disorder characterized by developmental delay, intellectual disability, and minor differences in facial features. Additionally, some people with this condition have recurrent seizures (epilepsy) or heart abnormalities that are present from birth (congenital heart defects).
  • 1.7K
  • 24 Dec 2020
Topic Review
Maple Syrup Urine Disease
       Maple Syrup Urine Disease (MSUD) is caused by a deficiency of branched-chain α-ketoacid dehydrogenase (BCKD). It is a metabolic disorder characterized by increased levels of branched-chain amino acids (BCAAs) and their respective branched-chain α-ketoacids (BCKAs) [1]. 
  • 1.7K
  • 26 Oct 2020
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