You have an error in your SQL syntax; check the manual that corresponds to your MariaDB server version for the right syntax to use near 'ASC limit 0,16' at line 14
SELECT r.PKResponsable, r.apellidos, r.nombre, r.HM, tp.tpPersInst, s.seudonimo FROM responsables r left join tipospersinst tp on tp.PKtpPersInst=r.FKtpPersInst left join seudonpersonas sp on sp.FKpersona=r.PKResponsable left join seudonimos s on s.PKseudonimo=sp.FKseudonimo WHERE r.FKtpPersInst in(84) group by r.PKResponsable ORDER BY ASC limit 0,16