Atle M. Bones Plant Genetics Group

INTRODUCTION

EWEN SWB & PUSZTAI A, 1999

Effects of diets containing genetically modified potatoes expressing Galanthus nivalis

lectin on rat small intestine, Lancet 354:1353-1355

BIOEMIT-SEMINAR 11-05-2004

Atle M. Bones Plant Genetics Group

Diets (feeding this diet for 10 days)

Parent: Potatoes. No gene modification. No added lectin

Parent +GNA: Potatoes+ added GNA lectin (25.4 ug/g)

GNA-GM: Gene modified potato expressing 25.4ug/g GNA lectin

GNA= Galanthus nivalis agglutinin (a lectin)

Outline of experiment:

Animals: Rats of ”similar weight” and age?

Data: 6 rats, 5 samples from each (stomach, jejunum, ileum, caecum amd colon)Mean value of 6 rats given +/- SD

Atle M. Bones Plant Genetics GroupMa etal, 2003NatRevGen4:794

Atle M. Bones Plant Genetics Group

Lectin expression:

Transgenic potato made by expression of a snow drop lectin (binds to alfa-1-3-mannose residues).

Fairly high level of lectin expression: 25.4 ug/g. Lectin containing edible plants normally have lectin levels of 0-10 ug/g. Some plants have lectin levels >5 mg/g

Atle M. Bones Plant Genetics Group

Digestive system:

Stomach/thin intestinal: Produces 17x109 cells/24h2-3 l HCl/day1.5 l bukspytt/day0.5 l galle/day1.5 l tarmsaft/day

Colon: 1 kg bacteria (+400 species)Absorbs 1.5 l ”water”/day

Atle M. Bones Plant Genetics Group

OverviewDigistive system

Samples from:

StomachJejunumIleumCaecumColon

Atle M. Bones Plant Genetics Group

Duodenum

Atle M. Bones Plant Genetics Group

Jejunum & ileum

Atle M. Bones Plant Genetics Group

Results:Significant differences in crypt length observed for:

Raw potatoes: Stomach: Parent vs Parent +GNA p= 0.03Jejunum:Parent+GNA vs GNA-GM p=0.01Caecum:Parent vs Parent +GNA p=0.02Colon:All significant different

Boiled potatoes:Caecum:Parent+GNA vs GNA-GM p= 0.04Colon:All significant different

Atle M. Bones Plant Genetics Group

Ewen & Pusztai’s resultater

Atle M. Bones Plant Genetics Group

Atle M. Bones Plant Genetics Group

Our body is prepared for digestion of plant food