单倍体植物（仅从一个亲代遗传染色体）在遗传研究中有重要优势，在植物育种中也极为重要――它们被用来生成纯合子二倍体，从而避免很多代的近亲繁殖。
现在，Maruthachalam Ravi 和 Simon Chan开发出一种通过种子来生成单倍体拟南芥的简单方法，该方法可以很容易被推广到农作物。以前，单倍体的生成涉及远交种的组织培养或基因组剔除，而且很多物种用这些方法是不可能培育出单倍体的。新方法涉及对一种蛋白（即“着丝点特异性组蛋白”，CENH3）用基因工程方法进行处理，生成在与野生型杂交后其基因组被从合子中除掉的品系。
这样产生的单倍体植物只有来自野生型亲代的染色体。CENH3在真核细胞着丝点上起普遍作用，所以原则上这种方法可以推广到所有植物。
生物谷推荐原文出处：
Nature doi:10.1038/nature08842
Haploid plants produced by centromere-mediated genome elimination
Maruthachalam Ravi1 " Simon W. L. Chan1
Department of Plant Biology, University of California, Davis, Davis, California 95616, USA
Production of haploid plants that inherit chromosomes from only one parent can greatly accelerate plant breeding1, 2, 3. Haploids generated from a heterozygous individual and converted to diploid create instant homozygous lines, bypassing generations of inbreeding. Two methods are generally used to produce haploids. First, cultured gametophyte cells may be regenerated into haploid plants4, but many species and genotypes are recalcitrant to this process2, 5. Second, haploids can be induced from rare interspecific crosses, in which one parental genome is eliminated after fertilization6, 7, 8, 9, 10, 11. The molecular basis for genome elimination is not understood, but one theory posits that centromeres from the two parent species interact unequally with the mitotic spindle, causing selective chromosome loss12, 13, 14. Here we show that haploid Arabidopsis thaliana plants can be easily generated through seeds by manipulating a single centromere protein, the centromere-specific histone CENH3 (called CENP-A in human). When cenh3 null mutants expressing altered CENH3 proteins are crossed to wild type, chromosomes from the mutant are eliminated, producing haploid progeny. Haploids are spontaneously converted into fertile diploids through meiotic non-reduction, allowing their genotype to be perpetuated. Maternal and paternal haploids can be generated through reciprocal crosses. We have also exploited centromere-mediated genome elimination to convert a natural tetraploid Arabidopsis into a diploid, reducing its ploidy to simplify breeding. As CENH3 is universal in eukaryotes, our method may be extended to produce haploids in any plant species.
