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Topic Review
Tubular Aggregate Myopathy
Tubular aggregate myopathy is a disorder that primarily affects the skeletal muscles, which are muscles the body uses for movement.
  • 1.2K
  • 23 Dec 2020
Topic Review
Bradykinin Hypothesis
Bradykinin (BK) (Greek brady-, slow; -kinin, kīn(eîn) to move) is a peptide that promotes inflammation. It causes arterioles to dilate (enlarge) via the release of prostacyclin, nitric oxide, and endothelium-derived hyperpolarizing factor and makes veins constrict, via prostaglandin F2, thereby leading to leakage into capillary beds, due to the increased pressure in the capillaries. Bradykinin is a physiologically and pharmacologically active peptide of the kinin group of proteins, consisting of nine amino acids. A class of drugs called angiotensin converting enzyme inhibitors (ACE inhibitors) increase bradykinin levels by inhibiting its degradation, thereby increasing its blood pressure lowering effect. ACE inhibitors are FDA approved for the treatment of hypertension and heart failure.
  • 1.2K
  • 14 Oct 2022
Topic Review
Snyder-Robinson Syndrome
Snyder-Robinson syndrome is a condition characterized by intellectual disability, muscle and bone abnormalities, and other problems with development. It occurs exclusively in males.
  • 1.2K
  • 23 Dec 2020
Topic Review
GEFS+
Genetic epilepsy with febrile seizures plus (GEFS+) is a spectrum of seizure disorders of varying severity.
  • 1.2K
  • 23 Dec 2020
Topic Review
Familial Isolated Hyperparathyroidism
Familial isolated hyperparathyroidism is an inherited condition characterized by overactivity of the parathyroid glands (hyperparathyroidism).
  • 1.2K
  • 25 Dec 2020
Topic Review
Sex-Chromosome Dosage Compensation
Dosage compensation is the process by which organisms equalize the expression of genes between members of different biological sexes. Across species, different sexes are often characterized by different types and numbers of sex chromosomes. In order to neutralize the large difference in gene dosage produced by differing numbers of sex chromosomes among the sexes, various evolutionary branches have acquired various methods to equalize gene expression among the sexes. Because sex chromosomes contain different numbers of genes, different species of organisms have developed different mechanisms to cope with this inequality. Replicating the actual gene is impossible; thus organisms instead equalize the expression from each gene. For example, in humans, females (XX) silence the transcription of one X chromosome of each pair, and transcribe all information from the other, expressed X chromosome. Thus, human females have the same number of expressed X-linked genes as do human males (XY), both sexes having essentially one X chromosome per cell, from which to transcribe and express genes. There are three main mechanisms of achieving dosage compensation which are widely documented in the literature and which are common to most species. These include random inactivation of one female X chromosome (as observed in Mus musculus; this is called X-inactivation), a two-fold increase in the transcription of a single male X chromosome (as observed in Drosophila melanogaster), and decreased transcription by half in both of the X chromosomes of a hermaphroditic organism (as observed in Caenorhabditis elegans). These mechanisms have been widely studied and manipulated in model organisms commonly used in the laboratory research setting. A summary of these forms of dosage compensation is illustrated below. However, there are also other less common forms of dosage compensation, which are not as widely researched and are sometimes specific to only one species (as observed in certain bird and monotreme species).
  • 1.2K
  • 20 Oct 2022
Topic Review
NRAS Gene
NRAS proto-oncogene, GTPase
  • 1.2K
  • 24 Dec 2020
Topic Review
Medically Assisted Reproduction
Since the birth of Louise Joy Brown, the first baby conceived via in vitro fertilization, more than 9 million children have been born worldwide using assisted reproductive technologies (ART). In vivo fertilization takes place in the maternal oviduct, where the unique physiological conditions guarantee the healthy development of the embryo. During early embryogenesis, a major wave of epigenetic reprogramming takes place that is crucial for the correct development of the embryo.
  • 1.2K
  • 27 Apr 2022
Topic Review
Gene annotation for 'Flaviviridae' genomes
Responding to the ongoing and severe public health threat of viruses of the family Flaviviridae, including dengue, hepatitis C, West Nile, yellow fever, and Zika, demands a greater understanding of how these viruses emerge and spread. Updated phylogenies are central to this understanding. Most cladograms of Flaviviridae focus on specific lineages and ignore outgroups, thus hampering the efficacy of the analysis to test ingroup monophyly and relationships. This is due to the lack of annotated Flaviviridae genomes, which has gene content variation among genera. This variation makes analysis without partitioning difficult. Therefore, we developed an annotation pipeline for the genera of Flaviviridae (Flavirirus, Hepacivirus, Pegivirus, and Pestivirus), named “Fast Loci Annotation of Viruses” (FLAVi: flavi-web.com), that combines ab initio and homology-based strategies. FLAVi recovered 100% of the genes in Flavivirus and Hepacivirus genomes. In Pegivirus and Pestivirus, annotation efficiency was 100% except for one partition each. There were no false positives. The combined phylogenetic analysis of multiple genes made possible by annotation has clear impacts over the tree topology compared to phylogenies that we inferred without outgroups or data partitioning. The final tree is largely congruent with previous hypotheses and adds evidence supporting the close phylogenetic relationship between dengue and Zika.
  • 1.2K
  • 27 Oct 2020
Topic Review
PEX1 Gene
peroxisomal biogenesis factor 1
  • 1.2K
  • 25 Dec 2020
Topic Review
VDR Gene
Vitamin D receptor
  • 1.2K
  • 04 Jan 2021
Topic Review
PPM-X Syndrome
PPM-X syndrome is a condition characterized by psychotic disorders (most commonly bipolar disorder), a pattern of movement abnormalities known as parkinsonism, and mild to severe intellectual disability with impaired language development.
  • 1.2K
  • 24 Dec 2020
Topic Review
Klinefelter Syndrome
Klinefelter syndrome is a chromosomal condition in boys and men that can affect physical and intellectual development.
  • 1.2K
  • 23 Dec 2020
Topic Review
Hypophosphatasia
Hypophosphatasia is an inherited disorder that affects the development of bones and teeth.
  • 1.2K
  • 23 Dec 2020
Topic Review
CLN3 Gene
CLN3, battenin
  • 1.2K
  • 24 Dec 2020
Topic Review
Obsessive-Compulsive Disorder
Obsessive-compulsive disorder (OCD) is a mental health condition characterized by features called obsessions and compulsions. Obsessions are intrusive thoughts, mental images, or urges to perform specific actions. While the particular obsessions vary widely, they often include fear of illness or contamination; a desire for symmetry or getting things "just right;" or intrusive thoughts involving religion, sex, or aggression. Compulsions consist of the repetitive performance of certain actions, such as checking or verifying, washing, counting, arranging, acting out specific routines, or seeking assurance. These behaviors are performed to relieve anxiety, rather than to seek pleasure as in other compulsive behaviors like gambling, eating, or sex.
  • 1.2K
  • 04 Jan 2021
Topic Review
Epigenetics
Changes in gene expression/phenotype without underlying DNA modification.
  • 1.2K
  • 21 Dec 2020
Topic Review
Spastic Paraplegia Type 2
Spastic paraplegia type 2 is part of a group of genetic disorders known as hereditary spastic paraplegias. These disorders are characterized by progressive muscle stiffness (spasticity) and the development of paralysis of the lower limbs (paraplegia). Hereditary spastic paraplegias are divided into two types: pure and complex. The pure types involve the lower limbs. The complex types involve the lower limbs and can also affect the upper limbs to a lesser degree; the structure or functioning of the brain; and the nerves connecting the brain and spinal cord to muscles and sensory cells that detect sensations such as touch, pain, heat, and sound (the peripheral nervous system). Spastic paraplegia type 2 can occur in either the pure or complex form.  
  • 1.2K
  • 23 Dec 2020
Topic Review
Gordon Holmes Syndrome
Gordon Holmes syndrome is a rare condition characterized by reproductive and neurological problems.
  • 1.2K
  • 23 Dec 2020
Topic Review
Proopiomelanocortin Deficiency
Proopiomelanocortin (POMC) deficiency causes severe obesity that begins at an early age. In addition to obesity, people with this condition have low levels of a hormone known as adrenocorticotropic hormone (ACTH) and tend to have red hair and pale skin.
  • 1.2K
  • 24 Dec 2020
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