Context : Globular clusters ( GCs ) are emerging as powerful tracers of the chemical composition of extragalactic stellar populations .

Aims : We present new abundance measurements for eleven GCs in the Local Group galaxies NGC 147 , NGC 6822 , and Messier 33 .
These are combined with previously published observations of four GCs in the Fornax and WLM galaxies .

Methods : The abundances were determined from analysis of integrated-light spectra , obtained with the HIRES spectrograph on the Keck I telescope and with UVES on the VLT .
We used our analysis technique that has been developed for this purpose and tested on Milky Way GCs .

Results : We find that the clusters with \mathrm { [ Fe / H ] } < -1.5 are all \alpha -enhanced at about the same level as Milky Way GCs .
Their Na abundances are also generally enhanced relative to Milky Way halo stars , suggesting that these extragalactic GCs resemble their Milky Way counterparts in containing significant fractions of Na-rich stars .
For \mathrm { [ Fe / H ] } > -1.5 , the GCs in M33 are also \alpha -enhanced , while the GCs that belong to dwarfs ( NGC 6822 SC7 and Fornax 4 ) have closer to Solar-scaled \alpha -element abundances .
The abundance patterns in SC7 are remarkably similar to those in the Galactic GC Ruprecht 106 , including significantly sub-solar \mathrm { [ Na / Fe ] } and \mathrm { [ Ni / Fe ] } ratios .
In NGC 147 , the GCs with \mathrm { [ Fe / H ] } < -2.0 account for about 6 % of the total luminosity of stars in the same metallicity range , a lower fraction than those previously found in the Fornax and WLM galaxies , but substantially higher than in the Milky Way halo .

Conclusions : At low metallicities , the abundance patterns suggest that GCs in the Milky Way , dwarf galaxies , and M33 experienced similar enrichment histories and/or processes .
At higher metallicities , the lower levels of \alpha -enhancement in the GCs found in dwarf galaxies resemble the abundance patterns observed in field stars in nearby dwarfs .
Constraining the presence of multiple populations in the GCs is complicated by the lack of information about detailed abundances in field stars of the corresponding metallicities .
We suggest that correlations such as \mathrm { [ Na / Fe ] } vs . \mathrm { [ Ni / Fe ] } may prove useful for this purpose if an accuracy of \sim 0.1 dex or better can be reached for the integrated-light measurements .