How gene shaped human face

Researchers from KU Leuven (Belgium) and the universities of Pittsburgh, Stanford, and Penn State (US) have identified fifteen genes that determine human facial features. Human DNA determines what an individual look like, including facial features. That appeals to the popular imagination, as the potential applications are obvious. Doctors could use DNA for skull and facial reconstructive surgery, forensic examiners could sketch a perpetrator's face on the basis of DNA retrieved from a crime scene, and historians would be able to reconstruct facial features using DNA from days long gone.

In a new study conducted by KU Leuven in collaboration with the universities of Pittsburgh, Stanford and Penn State, the researchers adopted a different approach. "Our search doesn't focus on specific traits," lead author Peter Claes (KU Leuven) explains. "My colleagues from Pittsburgh and Penn State each provided a database with 3D images of faces and the corresponding DNA of these people. Each face was automatically subdivided into smaller modules. Next, we examined whether any locations in the DNA matched these modules. This modular division technique made it possible for the first time to check for an unprecedented number of facial features."

The scientists were able to identify fifteen locations in human DNA. The Stanford team found out that genomic loci linked to these modular facial features are active when human face develops in the womb. "Furthermore, we also discovered that different genetic variants identified in the study are associated with regions of the genome that influence when, where and how much genes are expressed," says Joanna Wysocka (Stanford). Seven of the fifteen identified genes are linked to the nose, and that's good news, Peter Claes (KU Leuven) continues. "

A skull doesn't contain any traces of the nose, which only consists of soft tissue and cartilage. Therefore, when forensic scientists want to reconstruct a face on the basis of a skull, the nose is the main obstacle. If the skull also yields DNA, it would become much easier to determine the shape of the nose. Age, environment, and lifestyle have an impact on what human face looks like, this could provide genetic insight into the shape and functioning of human brain, as well as in neurodegenerative diseases such as Alzheimer's."
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Genetic mutations start after conception

Hundreds of minor genetic mutations start to form in the cells of an embryo after conception, some of these mutations occur as sex cells are forming in the embryo. That means they can become part of the embryo's genome and be passed on to the next generation.

This opens up a larger perspective on human development,  this shows that some of our genome does not come from our parents.These early genetic mutations are also similar to those found in cancers, cancers can occur as a normal byproduct of cell division, this mat be the causes of neurodevelopmental disorders such as schizophrenia or autism.

These conditions are primarily the result of genetic abnormalities, but no single gene inherited by parents has been found to cause a large number of cases.The study may also help explain why one identical twin might have a genetic disorder while the other is healthy, or why some members of a family who carry a disease-causing mutation do not get sick.
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Immune cells hinder metabolism in adult

Older people do not burn the energy stored in fat cells as efficiently as younger people, this leads to the accumulation of harmful belly fat. The underlying cause for this unresponsiveness in fat cells was unknown.

Researchers discovered a new type of macrophage that resides on the nerves in belly fat. These nerve-associated macrophages become inflamed with age and do not allow the neurotransmitters, which are chemical messengers, to function properly.
The researchers also isolated the immune cells from fat tissue of young and old mice, and then sequenced the genome to understand the problem.

They discovered that the aged macrophages can break down the neurotransmitters called catecholamines, and thus do not allow fat cells to supply the fuel when needed. Lowering a specific receptor that controls inflammation, the NLRP3 inflammasome, in aged macrophages, the catecholamines could act to induce fat breakdown, similar to that of young mice.

Researchers blocked an enzyme that is increased in aged macrophages, restoring normal fat metabolism in older mice, monoamine oxidase and MAOA, is prevented by existing drugs in the treatment of depression. When immune cell interact with nerves and fat cells to reduce belly fat, this enhance metabolism, improve performance and belly fat loss in older people.
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Three-dimensional organization of DNA

The three-dimensional organization of DNA in the nucleus influences our biology, from how our genome organized our cellular activity to how genes are passed from parents to children.

 X-rays and microscopy showed that the primary level of chromatin organization involves 147 bases of DNA spooling around proteins to form particles approximately 11 nanometers (nm) in diameter called nucleosomes.

These nucleosome "beads on a string" are then thought to fold into discrete fibers of increasing diameter (30, 120, 320 nm etc.), until they form chromosomes.

Researchers used ChromEMT to image and measure chromatin in resting human cells and during cell division (mitosis) when DNA is compacted into its most dense form -the 23 pairs of mitotic chromosomes that are the iconic image of the human genome.

Chromatin that has been extracted from the nucleus and subjected to processing in vitro - in test tubes - may not look like chromatin in an intact cell, so it is tremendously important to be able to see it in vivo.

Chromatin's packing density, and not some higher-order structure, that determines which areas of the genome are active and which are suppressed.

Controlling access to chromatin could be a useful approach to preventing, diagnosing and treating diseases like cancer.

Chromatin does not need to form discrete higher-order structures to fit in the nucleus, It's the packing density that could change and limit the accessibility of chromatin, providing a local and global structural basis through which different combinations of DNA sequences, nucleosome variations and modifications could be integrated in the nucleus to exquisitely fine-tune the functional activity and accessibility of our genomes.
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The 16 genetic markers associated with short lifespan

How long we will live is encoded in our genome. Researchers have identified 16 genetic markers associated with a short lifespan. This reveals computational framework to uncover the genetics of our time of death and disease. It explained why some people live longer than others. 

 About 30 percent of the variation in human lifespan comes down to our genome. Changes in particular locations in our DNA sequence, such as single-nucleotide polymorphisms (SNPs), could be responsible for some of the reasons for our longevity.

Changes in the DNA is linked to age-related diseases. About 1 in 10 people carry some configurations of these markers that shorten their life by over a year compared with the population average. Those who inherited a lifespan-shortening version of one of these SNPs may die earlier than their mate. 

The researchers explore how the DNA changes affected lifespan in a holistic way. They discovered that most SNPs had an effect on lifespan by impacting more than a single disease or risk factor, for example through being more addicted to smoking as well as through being predisposed to schizophrenia.

The discovered SNPs and gene expression data, allowed the researchers to identify that lower brain expression of three genes neighbouring the SNPs- RBM6, SULT1A1 and CHRNA5, involved in nicotine dependence was linked to increased lifespan. These three genes could therefore act as biomarkers for surviving beyond 100 years. 

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Any gene can influence diseases

Any gene can influence disease because
gene activity of cells is broadly interwoven. Some of the heritability of diseases is due to tiny contributions from some peripheral genes that function outside disease pathways.

Every gene in the genome influences everything about us, it may be little but they are part of the gene.
The researchers call their provocative new understanding of disease genes an "omnigenic model" to show that almost any gene can influence diseases.

In any cell, there might be 50 to 100 core genes with direct effects on a given trait, as well as easily another 10,000 peripheral genes that are expressed in the same cell with indirect effects on that trait.

 But because those thousands of genes outnumber the core genes by orders of magnitude, most of the genetic variation related to diseases and other traits comes from the thousands of peripheral genes.

The genes whose impact on disease is most indirect and small end up being responsible for most of the inheritance patterns of the diseases.

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Anorexia could be genetic

Anorexia is an eating disorder that makes  people to lose more weight than is considered healthy for their age and height.

People with this disorder are afraid of gaining weight, even when they are underweight. They may diet, exercise or use different methods to lose weight.

The study included genome-wide analysis of DNA from 3,495 individuals with anorexia nervosa and 10,982 unaffected individuals.

If particular genetic variations are significantly more frequent in people with a disorder compared to unaffected people, the variations are said to be related with the disorder.

Associated genetic variations can serve as powerful pointers to regions of the human genome where disorder-causing problems reside, according to the National Human Genome Research Institute.

Genome-wide significant locus for anorexia nervosa on chromosome 12, in a region previously shown to be associated with type 1 diabetes and autoimmune disorders.

Anorexia nervosa was significantly genetically correlated with neuroticism and schizophrenia. There is strong
genetic correlations with various metabolic features including body composition (BMI) and insulin-glucose metabolism.

New genetics locations of types 2 diabetes

Scientists from University College London and Imperial College London in the United Kingdom have identified new genetic locations that might make some people more prone to developing type 2 diabetes.

 Researchers were aware of 76 chromosomal locations before this discovery New research analyzed the human genome further and found an additional 111.

Dr. Nikolas Maniatis of University College London's (UCL) Genetics, Evolution, and Environment department, together with Dr. Toby Andrew of Imperial College London's Department of Genomics of common disease.

Using a UCL-developed method of genetic mapping, Maniatis and team examined large samples of European and African American people, summarizing 5,800 cases of type 2 diabetes and almost 9,700 healthy controls.

They found that the new location together with the old one control the expression of more than 266 genes surrounding the genetic location of the disease.

Most of the newly discovered location were found outside of the coding regions of these genes, but within so-called hotspots that change the expression of these genes in body fat.

Of the newly identified 111 locations 93 were found in European and African American population samples.
After identifying genetic location, the next step was to use deep sequence analysis to try to determine the genetic mutations responsible for the disease.

Gene mapping finds areas associated with diabetes - causing genetic location
Maniatis and colleagues used deep sequencing to further examine three of the cross-population locations with the aim of identifying the genetic mutations.

They then examined different sample of 94 Europeans with type 2 diabetes, as well as 94 healthy controls. Researchers
discovered that the three locations coincided with chromosomal regions that regulate gene expression, contain epigenetic markers, and present genetic mutations that have been suggested to cause type 2 diabetes.

Scientists discovered cancer-related gene mutation

Cancer starts with production of abnormal cell growth of genetic mutation.

Researchers from University of Maryland led by Thomas Peterson examined similar mutations that are all over genome.

They used genetic data to examined subcomponents of protein domain and discovered that each domain carries out different roles and still share the same protein domain.

Researchers focused on mutations in one region of specific genes and mutations in similar region across families of protein.

Data about somatic variants from 5,848 patients was collected with some patients having 20 different types of cancers.

Detecting variants for tumorigenesis will expose the cause of tumour progression leads to production of drugs for families of genes that shows similar variation at functional level.

Fast diagnosis for tuberculosis

Tuberculosis is an infectious bacteria disease that usually affects the lungs, it can also affects other parts of the body. It spreads through the air when an infected person talks, coughs, sneezes, yawns or laughs.

British scientists have discovered better ways of diagnosing tuberculosis by the use of genome sequencing to isolate different strains of the disease this leads to better and faster diagnosis  of tuberculosis and quick recovery.

Use of modern technology for treating tuberculosis  makes the patients to spend days for treatment instead of initial spending of months. This new development  can blot out tuberculosis from every parts of the world.