Estimados colegas, me parece que este punto de vista es necesario evaluarlo.
Saludos
Don Monroe*
When a gene works, evolution holds on to it, keeping its sequence
intact even as bases around it change over time. Genome researchers had
come to depend on this conservation to steer them to critical regions
in the genome: If a stretch of DNA remains unchanged across different
species, that DNA is probably performing a vital function. But a
growing number of examples show that not all conserved sequences are
important and, worse, that not all important sequences are conserved.
That second observation—which would have been considered heresy until
about a decade ago—means that researchers who had typically relied on
conservation to guide them could have missed critical genes or unknown
regulatory regions. But even as they scramble to understand how the
"conservation equals function" rule has failed them, they are
uncovering profound new subtleties in how genes are controlled and how
they adapt during evolution.
--
Dr. Humberto González
Márquez
Universidad Autónoma Metropolitana -
Iztapalapa
Depto. de Ciencias de la
Salud
San Rafael Atlixco
186
Edificio "S"- Lab.
248
A.P
55-535
09340 México,
DF
MEXICO
Tel. +(52 55) 58046557 FAX. +(52
55)58044727