Off topic:Keep special character in a .txt file

Question

[mostafarafiepour]

Hi all,

I have a .txt file including three columns which based on column Annotation, i want to keep only rows including synonymous and missense. I will be grateful if you can help me to solve this problem.

CHROM_POS       ANN     Annotation
CM009840.1_932          A|intergenic_region|MODIFIER|CHR_START-LOC112587351|CHR_START-gene0|||  nongenic
CM009840.1_1096         T|intergenic_region|MODIFIER|CHR_START-LOC112587351|CHR_START-gene0||   nongenic
CM009840.1_4421500      A|missense_variant|MODERATE|LOC102415844|gene14  |1/1|c.298C>T|p.Ar||   missense
CM009840.1_4421553      A|missense_variant|MODERATE|LOC102415844|gene14|transcript|rna37|p ||    missense
CM009840.1_4421600      G|synonymous_variant|LOW|LOC102415844|gene14|transcript|rna37|protei ||   synonymous
CM009840.1_4421630      C|synonymous_variant|LOW|LOC102415844|gene14|transcript|rna37|pro||   synonymous