Here's my path into investment research:

1. Graduated from local school. Top 5% of cohort. Finance related discipline
2. 3 years experience in banking line doing other front office roles (in bulge bracket)
3. No MBA

Advice: Timing. Luck and networking. Got the job purely because I knew the right people and waited for sometime till they had a headcount. This plus a personal recommendation from a friend to her boss.