1 research outputs found
Candidate Sequence Variants for Polyautoimmunity and Multiple Autoimmune Syndrome from a Colombian Genetic Isolate: Implications for Population Genetics
Autoimmunity is an immunological disorder whereby patients have
lost immunological tolerance to self-antigen. It has extreme
financial and socioeconomic burden with costs of over 100 billion
dollars in the USA alone, and an estimated prevalence of 9.4%,
and evidence indicates that this estimate has increased at a rate
of 5% per year for the past 3 years. These phenotypes can be
manifested in more severe forms through polyautoimmunity, whereby
patients are carrying 2 or more autoimmune conditions. In
addition to that, there is also the most extreme phenotype of
autoimmunity known as the Multiple Autoimmune Syndrome (MAS),
consisting of cases where patients have 3 or more autoimmune
diseases. These extreme phenotypes are extremely important for
genetic research as will be elaborated upon in this thesis. For
more than 20 years, pedigrees from the world’s largest known
genetic isolate, from the Paisa region of Colombia have been
ascertained and thoroughly followed by Dr. Juan-Manuel Anaya and
Dr. Mauricio Arcos-Burgos. This population has maintained its
status as a genetic isolate since the 16th century, during the
early colonization by the Spanish Conquistadors.
In this thesis, our attempts in identifying potential candidate
variants potentially underpinning the genetic etiology of
autoimmune conditions in this population is facilitated by the
fact that families are derived from individuals carrying extreme
phenotypes, from familial cohorts where genetic homogeneity is
maximized. Candidates are identified in both sporadic as well as
familial cases. This is primarily achieved through combination of
linkage analysis and association tests for both rare and common
variants, derived from variant-calling pipelines and that had
undergone quality control, filtering and functional annotation,
via bioinformatic anlayses. Genes harbouring variants with
significant evidence of linkage and association were primarily
involved in negative regulation of apoptosis, phagocytosis,
regulation of endopeptidase activity, response to
lipopolysaccharides and plasminogen urokinase receptor activity.
These findings, that were obtained by utilizing the combinations
of statistical as well as network-based analyses have relevant
potential implications in autoimmunity, and can be further
supported with additional studies