Lifeboat Foundation

FDA has authorized the Invitae Common Hereditary Cancers Panel, a blood test that detects inherited genetic changes that increase the risk of some cancers.

The advancement of higher cognitive abilities in humans is predominantly associated with the growth of the neocortex, a brain area key to conscious thinking, movement, and sensory perception. Researchers are increasingly realizing, however, that the “little brain” or cerebellum also expanded during evolution and probably contributes to the capacities unique to humans, explains Prof. Henrik Kaessmann from the Center for Molecular Biology of Heidelberg University.

His research team has – together with Prof. Dr Stefan Pfister from the Hopp Children’s Cancer Center Heidelberg – generated comprehensive genetic maps of the development of cells in the cerebella of humans, mice, and opossums. Comparisons of these data reveal both ancestral and species-specific cellular and molecular characteristics of cerebellum development spanning over 160 million years of mammalian evolution.

Genome and Structure:

HIV’s genome is a 9.7 kb linear positive-sense ssRNA.¹ There is a m⁷G-cap (specifically the standard eukaryotic m⁷GpppG as added by the host’s enzymes) at the 5’ end of the genome and a poly-A tail at the 3’ end of the genome.² The genome also has a 5’-LTR and 3’-LTR (long terminal repeats) that aid its integration into the host genome after reverse transcription, that facilitate HIV genetic regulation, and that play a variety of other important functional roles. In particular, it should be noted that the integrated 5’UTR contains the HIV promoter called U3.^3,4

HIV’s genome translates three polyproteins (as well as several accessory proteins). The Gag polyprotein contains the HIV structural proteins. The Gag-Pol polyprotein contains (within its Pol component) the enzymes viral protease, reverse transcriptase, and integrase. The Gag-Pol polyprotein is produced via a −1 ribosomal frameshift at the end of Gag translation. Because of the lower efficiency of this frameshift, Gag-Pol is synthesized 20-fold less frequently than Gag.⁵ The frameshift’s mechanism depends upon a slippery heptanucleotide sequence UUUUUUA and a downstream RNA secondary structure called the frameshift stimulatory signal (FSS).⁶ This FSS controls the efficiency of the frameshift process.

An MIT study suggests 3D folding of the genome is key to cells’ ability to store and pass on “memories” of which genes they should express.

Every cell in the human body contains the same genetic instructions, encoded in its DNA. However, out of about 30,000 genes, each cell expresses only those genes that it needs to become a nerve cell, immune cell, or any of the other hundreds of cell types in the body.

Each cell’s fate is largely determined by chemical modifications to the proteins that decorate its DNA; these modification in turn control which genes get turned on or off. When cells copy their DNA to divide, however, they lose half of these modifications, leaving the question: How do cells maintain the memory of what kind of cell they are supposed to be?

Continue reading “How cell identity is preserved when cells divide” »

Researchers at the Hubrecht Institute have laid the foundation for the development of a gene therapy for the genetic heart disease arrhythmogenic cardiomyopathy (ACM). Their approach, based on replacement of the PKP2 gene, led to significant structural and functional improvements in laboratory models of the disease.

The study by the group of Eva van Rooij was published on 7 December 2023 in Nature Cardiovascular Research. Multiple clinical trials will start in 2024 in the United States to explore the clinical potential of this approach in ACM patients with PKP2 mutations.

ACM is a genetic heart disease that affects 1 in 2,000 to 1 in 5,000 people worldwide. It is characterized by arrhythmias and can lead to sudden cardiac arrest. Current treatment of the disease usually consists of antiarrhythmic drugs and implantable cardioverter-defibrillators (ICDs), which are focused solely on treating the symptoms rather than targeting the root of the problem.

An international team led by researchers at the University of Toronto has uncovered over 100 genes that are common to primate brains but have undergone evolutionary divergence only in humans—and which could be a source of our unique cognitive ability.

The researchers, led by Associate Professor Jesse Gillis from the Donnelly Center for Cellular and Biomolecular Research and the department of physiology at U of T’s Temerty Faculty of Medicine, found the genes are expressed differently in the brains of humans compared to four of our relatives—chimpanzees, gorillas, macaques and marmosets.

The findings, published in Nature Ecology & Evolution, suggest that reduced selective pressure, or tolerance to loss-of-function mutations, may have allowed the genes to take on higher-level cognitive capacity. The study is part of the Human Cell Atlas, a global initiative to map all human cells to better understand health and disease.

In 2006, Paul Rothemund transformed the field of DNA nanotechnology when he unveiled an innovative approach for making shapes and patterns from genetic material.

On the internet, nothing is safe — not even your DNA, apparently.

That’s the dystopian lesson from the commercial genetic testing company 23andMe, which disclosed on Friday in a regulatory filing that hackers managed to access information on about 14,000 users or 0.1 percent of its customer user base.

But the problem goes beyond this relatively small number of people. Because the website allows users to share DNA information with other users in order to find relatives, the true number impacted is orders of magnitude larger — with about 6.9 million customers having their personal information compromised, according to TechCrunch. Big yikes on that figure, because it affects something like half of the 14 million users at 23andMe.

Scientists have created tiny, self-assembling robots made from human cells that could one day repair damaged skin and tissue.

These tiny biological machines, called Anthrobots, are made from human tracheal cells without any genetic modification. Lab dish experiments revealed they can encourage neurons, or nerve cells, to grow in damaged tissue.