3.1. Phylogenetic analysis of mtCOI gene
Sequence analysis of mtCOI resulted in identification of six
alleles present in tested samples and revealed that the haemocyte genome
does not correspond to the genome of the host animal in any clams
diagnosed with DN, whereas alleles in healthy animals represent the
exact same DNA sequence in both sample types. These results are
supported by high (>70) bootstrap values (Fig.
3.1 ).
Two mtCOI alleles, ‘a’ and ‘b’, consistent between host tissue
and haemolymph within an individual, were identified in healthy clams.
Alleles ‘c’, ‘e’, and ‘f’ discovered in solid tissue DNA of neoplastic
animals were not found in their haemolymph equivalents. Allele ‘d’
present in haemolymph of neoplastic animals was identical between all
four individuals diagnosed with DN and was distinct from both healthy
alleles and alleles found in the DNA of hosts with neoplasia. All
identified mtCOI alleles are listed in Tab. 3.1 .
3.2. Phylogenetic analysis ofEF1 αgene
Eight EF1α alleles were identified through sequence analysis and
cloning with the resulting tree supporting the mtCOI phylogenetic
analysis, showing variations between genomes of haemolymph and host
tissue in neoplastic clams (Fig. 3.2 ).
EF1α alleles ‘b’, ‘d’, and ‘h’ represent healthy host alleles, as
they were found to be identical between both DNA samples from healthyL. balthica individuals. EF1α allele ‘e’ was discovered to
be common in haemolymph DNA of all clams diagnosed with DN and was not
present or found at a much lower level in normal tissue samples. An
additional EF1α ‘g’ allele was detected in haemolymph sample from
#158 individual that was not present in the solid tissue of this
specimen, although it was found in tissue DNA of another neoplastic
clam. Two different alleles, ‘g” and ‘i’, were found in two neoplastic
hosts’ DNA (Tab. 3.2 ).