@titles = qw/Dr. Col. Miss/;  # list of allowable titles
$title_reg = join "|", @titles;
$title_reg =~ s/\./\\./g; # make sure the dots are literal

while (<>) {
  /
     ($title_reg)?  # optional title
     \s*            # skip any spaces
    (\S+)  \s+      # first name, skip following spaces
    ((?:\w\.\s*)+)? # middle initials - any number, optional
    (\S+)           # last name
  /iox;
  print "$1, $2, $3, $4\n";
}