GON4L and infertility disorder: Although we do not know if the male sterility at the LTMS locus is due to dominant genic male sterility caused by the Lebed allele alone or indica-japonica hybrid male sterility caused by interaction of the Lebed and T65 alleles, our study demonstrates that the heterozygous Lebed allele of the LTMS gene acts as a dominant sporophytic pollen killer in a nuclear background of japonica T65.