Ex Parte Lowe et al

Board of Patent Appeals and Interferences

Oct 30, 2009

10455229 (B.P.A.I. Oct. 30, 2009)

UNITED STATES PATENT AND TRADEMARK OFFICE
__________

BEFORE THE BOARD OF PATENT APPEALS
AND INTERFERENCES
__________

Ex parte BRENDA A. LOWE and PAUL S. CHOMET
__________

Appeal 2009-0036481
Application 10/455,229
Technology Center 1600
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Decided:2 October 30, 2009
__________

Before TONI R. SCHEINER, RICHARD M. LEBOVITZ, and
FRANCISCO C. PRATS, Administrative Patent Judges.

PRATS, Administrative Patent Judge.

DECISION ON APPEAL
This is an appeal under 35 U.S.C. § 134 involving claims to a method
for producing a transformable corn line. The Examiner has rejected the
claims as anticipated and obvious. We have jurisdiction under 35 U.S.C.
§ 6(b).

1 Monsanto Company is the real party in interest (App. Br. 2).
2 Oral argument was presented in this case on October 21, 2009.

Appeal 2009-003648
Application 10/455,229

We reverse.
STATEMENT OF THE CASE
Claims 1-10 are pending (see App. Br. 2). Claims 1-9 stand rejected
and are on appeal (id.). Claim 10 has been objected to as depending from a
rejected claim (id.).
Claim 1, the only independent claim, is representative of the appealed
subject matter and reads as follows:
1. A method for producing a transformable corn line
comprising introgressing at least one chromosomal locus
mapping to bin 6.02 to 6.04 or bin 10.04 to 10.06, wherein said
locus is introgressed from a more transformable corn line into a
less transformable corn line.

The Examiner cites the following documents as evidence of
unpatentability:
C.L. Armstrong et al., Development and availability of germplasm
with high Type II culture formation response, 65 MAIZE GENETICS
COOPERATION NEWSLETTER 92-93 (1991) (“Armstrong ‘91”).

C.L. Armstrong et al., Improved tissue culture response of an elite
maize inbred through backcross breeding, and identification of
chromosomal regions important for regeneration by RFLP analysis, 84
THEOR. APPL. GENET. 755-762 (1992) (“Armstrong ‘92”).

C.L. Armstrong et al., Field Evaluation of European Corn Borer
Control in Progeny of 173 Transgenic Corn Events Expressing an
Insecticidal Protein from Bacillus thuringiensis, 35 CROP SCIENCE 550-557
(1995) (“Armstrong ‘95”).

M. Lee et al., Genetic Analysis of Totipotency in Maize, 44TH ANNUAL
MAIZE GENETICS CONFERENCE 64, Poster No. 54:54 (2002).

The following rejections are before us for review:
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Claims 1-5 and 7-9 stand rejected under 35 U.S.C. § 102(b) as
anticipated by Armstrong ’92 (Ans. 3-4).
Claim 6 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Armstrong ’95 in view of Armstrong ’92 (Ans. 4-6).
ANTICIPATION
ISSUE
The Examiner cites Armstrong ’92 as disclosing “the successful
introgression of genes involved in the establishment of regenerable tissue
cultures from a more transformable corn line to a less transformable corn
line by backcross breeding” (Ans. 3). Specifically, the Examiner finds that
the chromosomal loci recited in claim 1 “would inherently be transferred to
the corn lines taught by Armstrong [‘92]” (id.).
The Examiner reasons that, because corn is a diploid species, an
ordinary artisan “would understand that when two corn plants are crossed
the progeny plants derived from such a cross will inherit one set of
chromosomes from one parent and the other set of chromosomes from the
other parent” (id. at 4). Therefore, the Examiner finds, the progeny of
Armstrong ‘92’s cross of the more transformable corn line, A188, with the
less transformable corn line, B73, “would inherently possess all ten corn
chromosomes, one set from each of A188 and B73 and therefore would
possess chromosomes 6 and 10” as required by claim 1 (id.).
Appellants argue that, although Armstrong ‘92’s progeny plants have
chromosomes 6 and 10, including the loci recited in claim 1, the reference
“does not expressly or inherently disclose a method for introgressing alleles
at the loci of the recited bins at chromosomes 6 and 10, which, as defined in
the Specification . . . and known in the art, requires multiple generations of
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selection and backcrossing for a specific locus” (Reply Br. 10). Thus,
Appellants urge, Armstrong ’92 only “describes crossing corn plants which
comprise chromosomes 6 and 10, but not any step of introgressing intervals
on chromosomes 6 and/or 10 as is claimed” (id.).
In view of the positions advanced by Appellants and the Examiner,
the issue with respect to this rejection is whether the Examiner erred in
concluding that Armstrong’s process results in “introgress[ion of] at least
one chromosomal locus mapping to bin 6.02 to 6.04 or bin 10.04 to 10.06,
wherein said locus is introgressed from a more transformable corn line into a
less transformable corn line,” as recited in claim 1.
FINDINGS OF FACT (“FF”)
1. Claim 1 recites a method for producing a transformable corn line.
The method includes the step of “introgressing at least one chromosomal
locus mapping to bin 6.02 to 6.04 or bin 10.04 to 10.06, wherein said locus
is introgressed from a more transformable corn line into a less transformable
corn line.”
It is undisputed that a chromosomal locus “mapping to bin 6.02 to
6.04” corresponds to a segment of maize chromosome 6, and that a
chromosomal locus mapping to “bin 10.04 to 10.06” corresponds to a
segment of maize chromosome 10.
2. The Specification explains the meaning of the term “transformable” as
follows:
A plant line, such as a maize inbred or hybrid, is said to
exhibit “enhanced transformability” if the transformation
efficiency of the line is greater than a parental line under
substantially identical conditions of transformation.
Transformation efficiency is a measure of the number of
transgenic plants regenerated relative to the number of units of
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starting material (for example, immature embryos, pieces of
callus and the like) exposed to an exogenous DNA, regardless
of the type of starting material, the method of transformation, or
the means of selection and regeneration. Under the breeding
and transformation conditions described herein, a line is
considered to exhibit enhanced transformability if a line
exposed to the breeding process has a higher transformation
efficiency tha[n] the starting parental line.

(Spec. 5.)
3. The Specification discloses that, in the inventors’ experience, “a
genotype may be culturable but not transformable. For example, immature
embryos were isolated from a number of elite corn lines and tested for
culturability and transformability; while a number of lines formed callus,
most of the lines were not transformable under the conditions employed”
(Spec. 2).
4. The Specification defines the term “introgress” as “[t]he process of
transferring genetic material from one genotype to another” (Spec. 30).
5. The Specification further defines introgression:
Introgression of a particular DNA element or set of
elements into a plant genotype is defined as the result of the
process of backcross conversion. A plant genotype into which
a DNA sequence has been introgressed may be referred to as a
backcross converted genotype, line, inbred, or hybrid.
Similarly a plant genotype lacking said desired DNA sequence
may be referred to as an unconverted genotype, line, inbred, or
hybrid.

(Spec. 19.)
6. The Specification describes the process of backcrossing, by which
introgression is achieved, as follows:
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Backcrossing transfers specific desirable traits, such as
the increased transformability QTL loci [quantitative trait loci]
of the current invention, from one inbred or non-inbred source
to an inbred that lacks that trait. This can be accomplished, for
example, by first crossing a superior inbred (A) (recurrent
parent) to a donor inbred (non-recurrent parent), which carries
the appropriate gene(s) for the trait in question . . . . The
progeny of this cross are then mated back to the superior
recurrent parent (A) followed by selection in the resultant
progeny for the desired trait to be transferred from the non-
recurrent parent. Such selection can be based on genetic assays,
as mentioned below, or alternatively, can be based on the
phenotype of the progeny plant. After five or more backcross
generations with selection for the desired trait, the progeny are
heterozygous for loci controlling the characteristic being
transferred, but are like the superior parent for most or almost
all other genes. The last generation of the backcross is selfed,
or sibbed, to give pure breeding progeny for the gene(s) being
transferred, in the case of the instant invention, loci providing
the plant with enhanced transformability.

(Spec. 18 (citation omitted).)
7. One claim-encompassed method of backcross conversion further
illustrates the process:
In one embodiment of the invention, the process of
backcross conversion may be defined as a process including the
steps of:
(a) crossing a plant of a first genotype containing one or more
desired gene, DNA sequence or element, such as the
[quantitative trait loci] of the present invention, to a plant of a
second genotype lacking said desired gene, DNA sequence or
element;
(b) selecting one or more progeny plant containing the desired
gene, DNA sequence or element;
(c) crossing the progeny plant to a plant of the second genotype;
and
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(d) repeating steps (b) and (c) for the purpose of transferring
said desired gene, DNA sequence or element from a plant of a
first genotype to a plant of a second genotype.

(Spec. 18-19.)
8. Armstrong ’92 discloses “the successful transfer of genes involved in
the establishment of regenerable tissue cultures from [the corn line] A188
(high responder; agronomically poor) into B73 (low responder;
agronomically elite) by backcross breeding” (Armstrong ’92 at 756).
9. Armstrong ’92 summarizes its methods as follows:
The frequency of initiation of friable, embryogenic callus
from immature embryos of the elite maize inbred line B73 was
increased dramatically by introgression of chromosomal
segments from the inbred line A188 through classical backcross
breeding. . . . The breeding scheme consisted of six generations
of backcrossing to B73 with selection at each generation for
high frequency initiation of embryogenic cultures. BC6
individuals were selfed for four generations to select
homozygous lines.

(Id. at 755 (emphasis added).)
10. Armstrong ’92 states that “RFLP analysis was used to determine the
locations and effects of the introgressed A188 chromosomal segments. Five
segments were retained through at least the fifth backcross generation” (id.
(emphasis added)).
11. Armstrong ’92 describes the RFLP analysis methods:
A total of 73 probes, distributed reasonably uniformly across
the ten chromosome complement of the maize genome, were
examined (Fig. 2). The maximum distance of any
chromosomal segment to the nearest RFLP marker was 36 map
units, and most regions were within 20 map units of a marker.
After five backcrosses, the RFLP marker-based estimate of
percent recovery of B73 was 95%. Assuming no further
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improvement in recovery with the sixth (final) backcross and
complete fixation of all A188 segments during the subsequent
selfing and selection, the minimum percent B73 recovery in the
BC6 S4 material is 90%.
The locations of chromosomal segments from A188 that
were maintained through at least the fifth backcross generation
are shown in Fig. 2.

(Id. at 757-758.)
12. Figure 2 of Armstrong ’92 shows that A188 chromosomal segments
were present on chromosomes 1, 2, 3, and 9 of the fifth backcross generation
(id. at 758).
PRINCIPLES OF LAW
“To anticipate a claim, a prior art reference must disclose every
limitation of the claimed invention, either explicitly or inherently.” In re
Schreiber, 128 F.3d 1473, 1477 (Fed. Cir. 1997).
During examination, the PTO must interpret terms in a claim using
“the broadest reasonable meaning of the words in their ordinary usage as
they would be understood by one of ordinary skill in the art, taking into
account whatever enlightenment by way of definitions or otherwise that may
be afforded by the written description contained in the applicant’s
specification.” In re Morris, 127 F.3d 1048, 1054 (Fed. Cir. 1997)
(emphasis added).
ANALYSIS
We agree with Appellants that the Examiner erred in concluding that
claim 1’s step of “introgressing at least one chromosomal locus mapping to
bin 6.02 to 6.04 or bin 10.04 to 10.06, wherein said locus is introgressed
from a more transformable corn line into a less transformable corn line”
(emphases added), encompasses the process described by Armstrong ’92.
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Contrary to the Examiner’s interpretation of the term, the
Specification explains that “introgressing” a chromosomal locus from a
more transformable corn line to a less transformable corn line means more
than merely crossing the two corn lines to produce a heterozygote with one
set of chromosomes from each parent. Rather, introgression requires
generating progeny that breed pure for the selected trait through backcross
conversion (see FF 6).
Thus, in addition to an initial cross between the two parents to
produce heterozygous progeny, to perform a chromosomal introgression the
heterozygotes must be backcrossed to the less transformable corn line, and
the resulting progeny selected for the desired trait associated with the locus
in question (FF 6, 7). According to the Specification:
After five or more backcross generations with selection
for the desired trait, the progeny are heterozygous for loci
controlling the characteristic being transferred, but are like the
superior parent for most or almost all other genes. The last
generation of the backcross is selfed, or sibbed, to give pure
breeding progeny for the gene(s) being transferred, in the case
of the instant invention, loci providing the plant with enhanced
transformability.

(Spec. 18 (FF 6).)
Like the Specification, Armstrong ’92 uses the terms “introgression”
and “introgressed” to describe the transfer of chromosomal segments, or
loci, from one corn line to another, using essentially the same backcross
conversion methods described in the Specification (FF 9, 10). Armstrong
’92 therefore provides evidence that an ordinary artisan would have
interpreted introgression to have the meaning provided in the Specification.
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We therefore agree with Appellants that an ordinary artisan would
have interpreted the introgressing step in claim 1 as requiring the use of
backcross conversion to produce “pure breeding progeny for the gene(s)
being transferred, in the case of the instant invention, loci providing the
plant with enhanced transformability” (Spec. 18 (FF 6)), with said loci
mapping to bin 6.02 to 6.04 and/or 10.04 to 10.06.
Thus, we do not agree with the Examiner that an ordinary artisan
would have considered Armstrong ’92’s initial cross of the A188 and B73
corn lines to be an “introgression” of A188 chromosomal loci into the B73
line, as that term is used in the claims. Nor do we agree with the Examiner
that Armstrong ’92 provides sufficient evidence to conclude that
chromosomal loci mapping to the sites on chromosomes 6 and 10 recited in
claim 1 were inherently introgressed from the A188 line to the B73.
Specifically, Armstrong ’92 discloses that the only chromosomal loci
that were actually “introgressed” were present on segments of chromosomes
1, 2, 3, and 9 (FF 12), which are not the loci recited in claim 1. This
disclosure is based on an RFLP analysis of the final generation using 73
probes described as being uniformly distributed across the plants’ ten
chromosomes, with the maximum distance of any chromosomal segment to
the nearest RFLP marker being 36 map units, and with most regions within
20 map units of a marker (FF 11).
The Examiner does not point to any evidence of record suggesting
that the analysis methods of Armstrong ’92 would have missed any
segments on either chromosome 6 or chromosome 10 that would have been
introgressed. We acknowledge the Examiner’s argument, that Armstrong
’92 inherently performed the step recited in claim 1 based on the disclosure
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of “introgression of genes involved in the establishment of regenerable
tissue cultures from a more transformable corn line to a less transformable
corn line” (Ans. 11).
However, the selection criteria in Armstrong ’92, the capacity of the
progeny to generate embryogenic callus from immature embryos (FF 9), is
distinct from the selection criteria for transformability, which is based on the
percentage of transgenic plants generated upon exposure to an exogenous
DNA (FF 2). Moreover, as pointed out in the Specification, a more easily
cultured plant is not necessarily more easily transformed (FF 3).
Thus, the fact that Armstrong ’92 was able to generate more readily
cultured plants does not show that loci conferring enhanced transformability
were necessarily, or inherently, introgressed from the A188 line to the B73
line. Moreover, the Examiner has not explained how the selection criteria in
Armstrong ’92 would necessarily select for progeny in which the loci recited
in claim 1 were introgressed from the A188 line to the B73.
In sum, in view of the disclosure in Armstrong ’92 that the only
introgressed chromosomal loci were not those recited in claim 1, and in view
of the Examiner’s failure to provide an adequate explanation as to why the
claimed chromosomal loci were necessarily “introgressed” from the A188
line into the B73 line, as an ordinary artisan would understand that term, we
agree with Appellants that the Examiner has not made a prima facie case of
anticipation sufficient to shift the burden of proving non-anticipation to
Appellants. We therefore also reverse the Examiner’s rejection of claim 1,
and its dependent claims 2-5 and 7-9, as being anticipated by Armstrong ’92.
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OBVIOUSNESS
Claim 6 stands rejected under 35 U.S.C. § 103(a) as being
unpatentable over Armstrong ’95 in view of Armstrong ’92 (Ans. 4-6).
Claim 6 recites “[t]he method of claim 1, wherein the transformability of
said corn lines is determined by microprojectile bombardment or
Agrobacterium-mediated transformation methods.”
The Examiner concedes that Armstrong ’92 does not describe
methods using microprojectile bombardment to transform corn plants, and
cites Armstrong ’95 for that proposition (Ans. 4). Based on the two
references’ teachings, the Examiner concludes that an ordinary artisan would
have considered it obvious to “modify the teachings of Armstrong et al
(1992) to use the method of microprojectile bombardment taught by
Armstrong et al (1995)” (id. at 5).
The Examiner reasons:
One of ordinary skill in the art would have been
motivated to combine the teachings of Armstrong et al (1992)
and Armstrong et al (1995) to produce a method of
introgressing chromosomal loci using microprojectile
bombardment because the use of microprojectile bombardment
has broadened the available germplasm base in corn and thus
the genetic improvement of corn is not solely dependent upon
genes available within sexually compatible species (see
Armstrong et al 1995, page 550, second column, last
paragraph). In addition, one of ordinary skill in the art would
have a reasonable expectation of success based on the success
of Armstrong et al (1995) in using microprojectile
bombardment to introgress insect resistant genes into corn (see
page 555, first column, second paragraph to page 556, first
column, end of first paragraph).

(Id. at 5-6.)
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We reverse this rejection as well. Claim 6 depends from claim 1, and
includes claim 1’s requirement of introgressing at least one chromosomal
locus mapping to bin 6.02 to 6.04 or bin 10.04 to 10.06 from a more
transformable corn line into a less transformable corn line. As discussed
above, we do not agree with the Examiner that Armstrong ’92 meets that
limitation.
The Examiner does not point to, and we do not see, any disclosure in
Armstrong ’95 that remedies the deficiencies of Armstrong ’92 with respect
to claim 1. Thus, because the Examiner has not adequately explained how
the cited references meet all of the limitations in claim 1, we reverse the
Examiner’s rejection of claim 6, which includes all of the limitations of
claim 1.

SUMMARY
We reverse the Examiner’s rejection of claims 1-5 and 7-9 under 35
U.S.C. § 102(b) as anticipated by Armstrong ’92.
We also reverse the Examiner’s rejection of claim 6 under 35 U.S.C. §
103(a) as being unpatentable over Armstrong ’95 in view of Armstrong ’92.

REVERSED

cdc

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