Isolation: fask04221 was identified in the 'l(2)k04221' line, which contains two P{lacW} insertions; P{lacW}k04221a and P{lacW}k04221b. Mapping indicates that fask04221 is not caused by either P{lacW} insertion.
Malpighian tubule buds appear globular and show defects in extension. The small intestine is small and misshapen. Large intestine cells lack polarity. The foregut is short and lacks the proventriculus. Midgut constrictions do not form. Head involution and dorsal closure are defective. There are holes in the epidermis. There is no invagination of the salivary gland or posterior spiracle.
The 'fas[1]' EMS allele and the 'P{PZ}05488' insertion were previously associated with the CG17716 gene, named 'faint sausage (fas)' (Lekven et al, 1998; FBrf0103312). However, a subsequent study has shown these alleles affect a different gene 'CG6197/fand' (Sauerwald et al, 2017; FBrf0234822). As far as can be ascertained, the 'fas[2]' (aka 'fas[IIA]') allele was defined by its failure to complement fas[1] and P{PZ}05488 (FBrf0041708, FBrf0103312) and so this allele has also been made an allele of CG6197/fand. 'fas[k04221]' was defined by its failure to complement fas[2] (FBrf0106865) and so this allele has also been made an allele of CG6197/fand.