echo "group_1
group_2
group_3" > input_file

echo "group_1 DATA ...
group_1 DATA ...
group_1 DATA ...
group_2 DATA ...
group_2 DATA ...
group_2 DATA ...
group_2 DATA ...
group_3 DATA ...
group_3 DATA ...
group_3 DATA ...
group_3 DATA ...
group_4 DATA ...
group_4 DATA ...
group_4 DATA ...
group_4 DATA ...
" > data_file

for var in $(cat < input_file)
do
  awk -v seq="$var" '{if (match($1, seq)) {print $0; found=1} else if (found) { printf "exit in %d row\n---\n", NR; exit }}' data_file
done