Potatoes bruises on the potatoes by lowering the

Potatoes genetically modified
to resist black spotting and high levels of acrylamide


         The web link I visited brought me to
the U.S. Food & Administration website. I was brought to a page listing
genetically engineered plants and crops that were improved to resist disease,
have improvement in growth, and resist fast ripening or bruising. I chose to
write about BNF No. 152. The plant that was genetically engineered was the
potato. The developer, J.R. Simplot, called it the V11 potato. Simplot
developed this potato using recombinant DNA techniques.

         The gene segments aimed to be reduced
or silenced were from PPO5 gene, ASN1 gene, and R1 and PhL promoters. The gene
segment from PPO5 gene encodes polyphenol oxidase 5 and its source is solanum
verrucosum. The function of PPO5 is to catalyze o-quinone and o-diphenols which
polymerize to form melanin. If PPO5 is reduced, the coloration of oxidized
tissue is reduced. The purpose of introducing this gene segment was to prevent
black spot bruises on the potatoes by lowering the endogenous enzyme levels.
The second trait introduced to the V11 potato are gene segments from the ASN1
gene which encodes asparagine synthase1. The source of the ASN1 gene segment
was Solanum tuberosum var. Ranger Russet and this segment reduced levels of
free asparagine in the potato plant. The last trait introduced was from R1 and
PhL promoters. The source was also Solanum tuberosum var. Ranger Russet. The
PhL gene encodes phosphorylase that degrades starch by a release of a glucose
phosphate gene. A reduction of PhL lowered levels of reducing-sugars which
lowers the forming of acrylamide when heated. The R1 gene encodes a starch R1
gene that accelerates phosphates ATP. It is responsible for phosphorylation
which packs crystalline within starch and becomes more attainable to
degradation. The loss of R1 impairs this process and reduces accumulation of
reducing sugars.

         The overall purpose J.R. Simplot Company
genetically modified their potatoes was so that they contain less asparagine
that turns into acrylamide during the frying of potatoes and to prevent black
spot bruising. The developer company and the FDA have both concluded that the
V11 potato is safe for consumption and is not different in composition from
other potatoes on the market. However, since 93% of potatoes are used for human
food there are concerns about the effects of high levels of free asparagine upon
heating of the potatoes. The free asparagine can have a reaction to reducing
sugars and can cause a safety concern. This is why the V11 potato has to be
correctly genetically modified in order to avoid these adverse effects.

          There has been other research works
about the ASN1 gene and its reduction to produce less of acrylamide in heat.  Acrylamide is produced in foods while cooking
with high temperatures. Acrylamide has introduced health concerns. Fried
potatoes contain an immense amount of acrylamide. One way to inhibit acrylamide
is to attain potato cultivars that have little contents of asparagine. Plant
Biotechnol generated a number of silencing lines of potato by targeting genes
ASN1 and ASn2. The transcription levels of the gene were closely tied with
reducing sugar and asparagine content. Fried potatoes from ASN1/ASN2 silencing
lines contained only one-fifteenth of the acrylamide content. In conclusion, acrylamide
mitigation strategy on developing potato cultivars with low reducing sugars is
probable to be a plentiful approach for minimizing the acrylamide formation potential
of fried potatoes.