ஐ.எஸ்.எஸ்.என்: 2456-3102
Sara da Silva Nascimento,Pierre Teodósio Félix*
Biosensors are small devices that use biological reactions to detect target analytes. Such devices combine a biological
component with a physical transducer, which converts bio-recognition processes into measurable signals. Its use
brings a number of advantages, as they are highly sensitive and selective, relatively easy in terms of development,
as well as accessible and ready to use. Biosensors can be of direct detection, using a non-catalytic ligand, such as
cell receptors and antibodies, or indirect detection, in which there is the use of fluorescently marked antibodies
or catalytic elements, such as enzymes. They also appear as bio-affinity devices, depending only on the selective
binding of the target analyte to the ligative attached to the surface (e.g., oligonucleotide probe). The objectives were
to evaluate the levels of genetic diversity existing in fragments of the TP53 gene deposited in molecular databases
and to study its viability as a biosensor in the detection of breast cancer. The methodology used was to recover and
analyze 301 sequences of a fragment of the TP53 gene of humans from GENBANK, which, after being aligned
with the MEGA software version 6.06, were tested for the phylogenetic signal using TREE-PUZZLE 5.2. Trees of
maximum likelihood were generated through PAUP version 4.0b10 and the consistency of the branches was verified
with the bootstrap test with 1000 pseudo-replications. After aligning, 783 of the 791 sites remained conserved.
The maximum likelihood had a slight manifestation since the gamma distribution used 05 categories + G for the
evolutionary rates between sites with (0.90 0.96, 1.00, 1.04 and 1.10 substitutions per site). To estimate ML values,
a tree topology was automatically computed with a maximum Log of -1058,195 for this calculation. All positions
containing missing gaps or data were deleted, leaving a total of 755 sites in the final dataset. The evolutionary
history was represented by consensus trees generated by 500 replications, which according to neighbor-join and
BioNJ algorithms set up a matrix with minimal distances between haplotypes, corroborating the high degree of
conservation for the TP53 gene. GENE TP53 seems to be a strong candidate in the construction of Biosensors for
breast cancer diagnosis in human populations.