Chicken egg knocked out allergies

Allergy to chicken eggs is widespread and is one of the most common and pronounced food allergies in children. 

The main allergens in chicken eggs are ovomucoid (OVM), ovalbumin, ovotransferrin and lysozyme proteins, among which OVM is the most prevalent allergenic protein.

While the other allergenic proteins mentioned can be inactivated or denatured by treatment with heat or digestive enzymes, ovomucoid persists even after treatment. 

It should be noted that chicken eggs are now used in pharmaceuticals: a growing chicken egg is used to produce vaccines against influenza and yellow fever. Therefore, chicken eggs devoid of the ovomucoid allergen can be effectively used for vaccine production and administered to patients with egg allergy.

Now geneticists have found a way to eliminate the allergy at its source by changing the genetics of laying hens. Their method used "platinum" effector nucleases, similar to transcription activators (TALEN), but with higher DNA cleavage activity. These proteins help in cutting and thus changing the DNA. 

A team of Japanese scientists removed the ovomucoid gene from lab-grown roosters and then crossed the chimeric males with laying hens to produce eggs. Target offspring of ovomucoid knockout hens derived from male germline chimeras produced OVM-null eggs.

Ryo Ezaki, Tetsushi Sakuma, Daisuke Kodama, Ryo Sasahara, Taichi Shiraogawa, Kennosuke Ichikawa, Mei Matsuzaki, Akihiro Handa, Takashi Yamamoto, Hiroyuki Horiuchi worked on the creation of the OVM-zero egg and published a corresponding article in the journal Food and Chemical Toxicology. This work was supported by the Japanese Society for the Promotion of Science KAKENHI.