Rescuing Children Born Without Immune Systems With HIV Gene Therapy Methods

    Experimental gene therapy leads to 48 out of 50 young children born without immune systems being able to acquire an essentially normal immune system.  Children born without an immune system can experience life-threatening illnesses from simple day-to-day activities. 50 of the young children had a form of immune deficiency called ADA-SCID. This is where a faulty gene causes a buildup in the bloodstream with a common and natural biochemical called adenosine. By utilizing experimental gene therapy inside a newborn's body the genetic defect that causes immune deficiency is able to be fixed. The procedure uses a modified, harmless version of AIDS-causing human immunodeficiency virus (HIV) in order to cure the patient.  During the procedure, doctors extract some of a child's bone marrow and expose it to a modified version of HIV containing a cloned, normal copy of their broken gene. "We collect blood-forming stem cells from the bone marrow of these patients, bring them to the laboratory, use this lentiviral vector to insert this normal gene into their stem cells, and then they're given back to the patients by intravenous infusion," said lead researcher Dr. Donald Kohn. Then children undergo chemotherapy to destroy their faulty bone marrow, and the new genetically modified cells are put back in as a replacement. Children who have had this procedure have not needed any other medical assistance pertaining to their previous immune deficiency after the gene therapy.

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Gene Therapy Uses HIV to Rescue Kids Born Without Immune System

Adenosine deaminase deficiency

By Katherine Morone

Mosquito preference for human versus animal biting has genetic basis

Bradley Main, a researcher at the UC Davis School of Veterinary Medicine along with his colleagues investigated whether there is a genetic basis to host choice and resting behavior in Anopheles arebiensis. That species of mosquito has been the primary cause of malaria in East Africa where there are a lot of pesticide-treated bed nets that kill other species which live closely with humans. Using genetics, the team of researchers led by Main have established an association between human feeding and a specific chromosomal rearrangement in the major East African malaria vector. This work enables them to determine the specific genes that are involved in this important trait. Using genetics to better understand mosquito behavior could pave ways to stop malaria from spreading as well as genetically modify mosquitoes to prefer cattle rather than humans.

The researchers were able to sequence the genomes of 23 human-fed and 25 cattle-fed mosquitoes collected indoors and outdoors from the Kilobero Valley in Tanzania. They then identified a genetic component of the mosquito that contributes to its host choice. They were able to narrow down the region of the genes involved in cattle feeding to a chromosomal rearrangement called the 3Ra inversion. This study is the first to use genomic tools to provide a genetic basis as to why mosquitoes prefer cattle over humans. While the observations and data provide strong support that the inversion is linked to cattle feeding, the team needs to test a larger geographic area to ensure the results are true.

This was a very interesting article. By narrowing down the genes involved in cattle feeding to a chromosomal rearrangement, scientists are one step closer to helping prevent the spread of malaria in humans and genetically modify mosquitoes to prefer cattle over humans. Once the team tests a larger geographic area and gets their results, it could essentially save a lot of lives in Africa through such a large advancement in science and technology.