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From:
"Valerie W. McClain, IBCLC" <[log in to unmask]>
Reply To:
Lactation Information and Discussion <[log in to unmask]>
Date:
Thu, 8 Aug 2002 06:56:52 EDT
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In genetic engineering, human milk proteins may be produced from various
microorganisms such as e.coli and some yeasts (candida being one organism
they use).  Genetic engineering also uses antibiotic restriction enzymes as
markers, thus we are combining supposedly innocuous pathogens with
antibiotics to produce human proteins. (more complicated than this
description).  Biotechnologists do not believe that any kind of
transformation (to more virulent pathogens) can occur in the human gut.
Although there are some scientists who do believe that this is possible and
predictable.  Who is monitoring whether this is happening?  I believe infant
formulas and particularly preterm formulas have been genetically engineered
for some time.  Is this rise in e.coli and candida infections a natural
occurrence or is this new "food" science creating some resistant pathogens?
Many of the scientists who question this technology have either lost their
jobs or have been demoted or receive no funding.  Thus any criticism (which
good science thrives on) of this new technology has been effectively silenced.

Here is a patent that I think people should read to get a further
understanding of what is in infant formula and preterm formula (this patent
is intended for term as well as preterm formula). It is interesting that some
women have donated epithelial cells from their mammary glands in this patent
(and in other patents, too).  Donated to a Cancer Foundation who must have
"given" it to research and the researcher gets to patent from this donated
tissue to make infant formula.  But then donated milk from human milk banks
has been used for other patents.  We, woman, are such generous souls.  We
give it away in hopes to help some poor woman or baby, while some men make
money off it.  Guess there is no question why men make more money than women,
we, women, give everything away.
Valerie W. McClain, IBCLC

http://www.uspto.gov/patft/index.html
This patent was filed in 1989 but not accepted until 1998.
Patent # 5795611 called "Human infant formulas containing recombinant human
alpha-lactalbumin and beta-casein."
inventor:  Slattery

"Preparation of a cDNA Library

To produce human alpha-lactalbumin and beta-casein in microorganisms,
epithelial cells from the human mammary gland must be obtained which may be
treated with hormones, such as prolactin, to induce protein synthesis.
Appropriate cell lines are commercially available from a variety of sources,
such as the Michigan Cancer Foundation. From the prolactin treated cells,
mRNA may be obtained by isolating total RNA (J. M. Chirgwin, A. E. Przybyla,
R. J. MacDonald and W. J. Rutter, Biochemistry, 18, 5294-5299 (1979)), and
then the poly (A)+RNA fraction (H. Avis and P. Leder, Proc. Natl. Acad. Sci.,
69, 1408-1412 (1972)). Single and double stranded cDNA are prepared from this
(U. Gubler and B. J. Hoffman, Gene, 25, 263-269 (1983)), followed by ligation
and transfection to construct the library, ("Current Protocols in Molecular
Biology", F. M. Ausubel, R. Brent, R. E. Kingston, D. D. Moore, J. G.
Seidman, J. A. Smith and K. Struhl, editors, John Wiley and Sons, New York
(1987)) with subsequent isolation of the particular genes.

As an alternative procedure, a commercial cDNA library (HZ1037) is available
from Clontech Labs, Inc. (Palo Alto, Calif.), prepared from human mammary
tissue cells from a woman 8 months pregnant. Such a cDNA library has been
used (Menon and Ham, J. Cell Biol., 107, 523a (1989); S. Menon and R. G. Ham,
Nucl. Acids Res., 17, 2869 (1989)) to prepare, clone and sequence human
beta-casein cDNA.

Gene Synthesis

The complete amino acid sequence is known for both alpha-lactalbumin and
beta-casein: ##STR1## (R. Greenberg, M. L. Groves and H. J. Dower. J. Biol.
Chem. 259, 5132-5138 (1984))

From a knowledge of the genetic code, the sequence of the nucleic acids in
the genes for these proteins may be deduced and the genes themselves produced
synthetically. The length of the genes, with three nucleotides per amino acid
residue, is within the capabilities of properly equipped laboratories to
synthesize. In addition, the ends of the nucleotide chain comprising the gene
may be designed for proper incorporation into a chosen plasmid for insertion
into the microorganism and may include a start or stop codon. In the example
described here, a start codon would not be needed but the sequence should end
with a stop codon, such as UAA, and an unpaired sequence, complementary to
the restriction endonuclease site, which is "sticky."

These genes are capable of introduction into a recipient strain by means of
transformation or transfection followed by replication and amplification. The
vector molecules used are plasmid DNA or DNA of temperate bacteriophages,
viruses or other self-propagating DNA. Many of these methods are described in
detail in the following publications:

1. Cohen, S. N.; Chang, A. C. Y; Boyer, H. W. and Helling, R. B. (1973) Proc.
Nat. Acad. Sci. USA, 70, 3240.

2. Green, P. J.; Betlach, M. D.; Boyer, H. W. and Goodman, H. N. (1974)
Methods in Molecular Biology, 7, 87.

3. Tanaka, T. and Weisblum, B. (1975) J.Bacteriol, 121, 354.

4. Clarke, L. and Carbon, J. (1975) Proc. Nat. Acad. Sci. USA, 72, 4361.

5. Bolivar, F.; Rodrigues, R. L.; Green, P. J.; Betlach, M. C.; Heyneker, H.
L. and Boyer, H. W . (1977) Gene, 2, 95.

6. Kozlov, J. I.; Kalinina, N. A.; Gening, L. V.; Rebentish, B. A.; Strongin,
A. J.; Bogush, V. G. and Debabov, V. G. (1977) Molec. Gen. Genetics, 150,
211.

Introduction of Promoter Sequences

Different organisms, of course, recognize different promoter sequences.
Therefore, various new promoter sequences appropriate for different host
bacteria or yeasts may be introduced onto the genes coding for
alpha-lactalbumin and/or beta-casein into a unique site in the vector and for
introducing the assembled DNA sequence into a variety of cloning vectors.
Alternatively, the new promoter may be introduced via a particular
restriction endonuclease site in the plasmid which allows for insertion of
the sequence into the genome of any of a variety of appropriate host bacteria
or yeast the genes calling for human alpha-lactalbumin or beta-casein. The
following are a representative list of hosts and promoters: "



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