  The study of ages, helium mass fraction (Y) and chemical composition of
globular clusters in dwarf galaxies is important for understanding the physical
conditions at the main evolutionary stages of the host galaxies and for
constraining the build-up histories of large galaxies. We present the analysis
of integrated-light spectra of 8 extragalactic and 20 Galactic globular
clusters (GCs) using our population synthesis method. We calculate synthetic
spectra of GCs according to the defined stellar mass functions using model
atmospheres and stellar parameters ($[Fe/H]$, $T_{eff}$, and $log g$) set by
theoretical isochrones. The main advantage of our method is the ability to
determine not only chemical composition but also the age and mean Y in a
cluster by modelling and analysis of Balmer absorption lines. The knowledge of
Y and anomalies of light elements in star clusters is one of the key points for
understanding the phenomenon of multiple stellar populations.
