Gene therapy for blood disorder may be effective

Gene therapy for patients with a severe form of the blood disorder beta-thalassaemia could be safe and effective as well as end the need for transfusions, results from the clinical trials show.


Beta-thalassaemia is a genetic disorder that impairs the body's ability to produce a key component of haemoglobin — a critical protein in red blood cells that carries oxygen to organs and tissue.

People with the most severe forms of beta-thalassaemia require monthly blood transfusions, right from their toddler age, to replenish their red blood cell supplies along with iron chelation to remove extra iron from the body.

Frequent transfusions, however, can cause serious complications due to iron toxicity and viral infections.

The results showed that a one-time treatment with the gene therapy known as LentiGlobin BB305 vector reduced or eliminated the need for blood transfusions in 22 patients with severe beta-thalassaemia.

 We saw remarkable outcomes using LentiGlobin gene therapy, with most patients no longer needing monthly transfusions, said lead author .

 'These study results exceeded our expectations with clinical benefit for nearly all patients and suggest that gene therapy may be an effective treatment for thalassaemia in the future, he added.

Of the 22 patients aged between 12 and 35 years, 15 patients achieved transfusion-free status, while others needed transfusions less often.

All the patient underwent chemotherapy, after which they were infused with their own stem cells that were treated in the lab with a modified virus to replace the gene that is defective in thalassaemia. Patients typically reached peak production of haemoglobin in 9-12 months after infusion.

'While these gene therapy trials were the largest for thalassaemia to date, we need to evaluate effectiveness in a much larger population, the author said, adding that they 'are now enrolling patients as young as five-years-old on a Phase 3 trial.

THIS IS ONLY FOR INFORMATION, ALWAYS CONSULT YOU PHYSICIAN BEFORE HAVING ANY PARTICULAR FOOD/ MEDICATION/EXERCISE/OTHER REMEDIES.                                                                                                                                                                                                        PS- THOSE INTERESTED IN RECIPES ARE FREE TO  VIEW MY BLOG-                                                                                           https://gseasyrecipes.blogspot.com/  

FOR INFO ABOUT KNEE REPLACEMENT, YOU CAN VIEW MY BLOG-                                                                                                                              https:// kneereplacement-stickclub.blogspot.com/                              
FOR CROCHET DESIGNS                                                                                                                                                                                                                                 https://my crochet creations.blogspot.com  

A Fatal Blood Disorder Was Fixed in an Embryo Using Precision Gene Editing

In the wake of the first gene-edited embryo being created earlier this year, researchers have employed a different technique to swap a single base in a human embryo's genome.

The precise edit was designed to return functionality to a gene responsible for a component of hemoglobin, which in its mutated form results in an often fatal blood condition called beta-thalassaemia.

A team of researchers used what's called a base editor technique to change a single G back to an A in the DNA code of an embryonic cell's HBB gene.

The change might have been tiny, but in its mutated form HBB can't produce the protein beta-globin needed to build the oxygen-carrying hemoglobin for our red blood cells.

A shortage of hemoglobin means a shortage of oxygen, impeding growth and development and leading to a lifetime of blood transfusions to treat anaemia – if the embryo survives at all.

Beta-thalassaemia is usually a recessive condition, meaning both parents need to contribute a copy of the mutated gene for anaemia to develop in their child.

Correcting the mutations in this gene could help parents carry an embryo to term, or remove the trait from family lines.

About 400 different kinds of code-corruptions can affect HBB.

In this case, the researchers focused on a single point-mutation that targets a base called cytosine (C) and exchanges it for one called thymine (T).

Each of these letters complements the other two kinds of base – thymine is a jigsaw-puzzle piece that matches adenine (A), while cytosine matches guanine (G).

By swapping a C for a T, the mutation should revert back to the proper 'A' code.

If this base editing technology seems unnecessarily complicated, there's a good reason for doing a genetic do-si-do – it means the strand of DNA isn't being snipped all the way through.

To test if the procedure was feasible, the team created a cell line with pieces of the gene embedded inside and then used two different base editing techniques to change the code.

Satisfied the editing could be done, they took the process to the next level and edited the gene in skin cells from a beta-thalassemia patient.

Researchers transferred the nucleus of the patient's skin cells into 30 mature oocytes – or human egg cells.

One of the techniques was then applied to the 26 cells that survived the cloning procedure, which successfully turned the G to an A in 9 of the embryos, and a G to a C (cytosine) in one.
None of the embryos were developed further or implanted.

Gene editing has been big news in recent years with advances in the application of a technology called CRISPR, which uses enzymes found in bacteria to chew up DNA at a specific location.

Applying this kind of corrective genetic surgery to human embryos could spell an end to a variety of inherited conditions, but so far efforts have been controversial, to say the least.

Questions have developed  recently on whether or not the technology produces unwanted mutations, indicating that for all of its promise, it's still early days for this revolutionary engineering tool.

Base editing won't replace CRISPR, but could be a more delicate solution for those solitary mutations.

"We are the first to demonstrate the feasibility of curing genetic disease in human embryos by base editor system," researcher said.

Feasibility is the word here. We're nowhere near a safe operating procedure for repairing genes we consider broken in embryos.

But each careful step, coupled with healthy public debate, brings us a bit closer to an age when debilitating conditions like beta-thalassemia will be notes in a medical history book.

THIS IS ONLY FOR INFORMATION, ALWAYS CONSULT YOU PHYSICIAN BEFORE HAVING ANY PARTICULAR FOOD/ MEDICATION/EXERCISE/OTHER REMEDIES. PS- THOSE INTERESTED IN RECIPES ARE FREE TO VIEW MY BLOG-                      

HTTP:GSEASYRECIPES.BLOGSPOT.COM/
FOR INFO ABOUT KNEE REPLACEMENT, YOU CAN VIEW MY BLOG-                                                                           

HTTP://KNEE REPLACEMENT-STICK CLUB.BLOGSPOT.COM/
FOR CROCHET DESIGNS
HTTP://MY CROCHET CREATIONS.BLOGSPOT.COM