The Scottish fund manager Baillie Gifford, which has grown into one of the UK's largest investment firms in the past few years, is to lose its longest-serving partner at the end of April.

Sarah Whitley, head of Baillie Gifford's Japanese equities team, is standing down that month after 37 years with the firm. She has managed the £658m Baillie Gifford Japan Trust since 2001, and co-managed the £1.9bn Japanese Fund since 2007.