Regex: matching from a specified word to just before a specified word

Question

The following are my strings:

1. NM_001002.4 Homo sapiens ribosomal protein lateral stalk subunit P0 (RPLP0) transcript variant 1, mRNA
2. NM_181528.3 Homo sapiens N-alpha-acetyltransferase 20, NatB catalytic subunit (NAA20), transcript variant 3, mRNA

I am using the following regex command in python: (Homo sapiens [^,]*)

outcome: Homo sapiens ribosomal protein lateral stalk subunit P0 (RPLP0) transcript variant 1 Homo sapiens N-alpha-acetyltransferase 20

expected outcomes are:

Homo sapiens ribosomal protein lateral stalk subunit P0 (RPLP0) transcript variant 1

Homo sapiens N-alpha-acetyltransferase 20, NatB catalytic subunit (NAA20), transcript variant 3

Kindly help me. Thanks in advance!

Answer 1

1. If 'transcript variant' is always present in the data:

    (Homo sapiens.* transcript variant [^,]*)

2. If ', mRNA' is always present in the data:

    (Homo sapiens.*)(?:, mRNA)

   and get group1