To date molecular data have not revealed the exact phylogenetic position of Balanophoraceae in relation to hemiparasitic Santalales. To elucidate the phylogeny of Santalales and the position of Balanophoraceae, three plastid genes (matK, rbcL, accD), three nuclear genes (SSU and LSU rDNA and RPB2) and one mitochondrial gene (matR) from 197 Santalales samples (including 11 Balanophoraceae species) were analyzed with parsimony, maximum likelihood and Bayesian inference methods. Our results demonstrate that Balanophoraceae is composed of two well‐supported clades: a relatively slow‐evolving one including Dactylantus, Hachettea, and Mystropetalon (Mystropetalaceae) and an extremely fast‐evolving one composed of the remaining Balanophoraceae s.str. Support for monophyly of the two clades was low, thus it appears holoparasitism has arisen twice independently in Santalales. These two clades appeared during a time of great change in the order (ca. 100 Ma) when several major evolutionary innovations emerged, e.g., the root hemiparasites of Santalaceae s.l., the first aerial parasites (Misodendraceae), herbaceous root parasites (Schoepfiaceae), root parasitic Loranthaceae (the ancestors of aerial parasitic mistletoes), as well as the holoparasites in Balanophoraceae and Mystropetalaceae.

The reference sequence for each human chromosome provides the framework for understanding genome function, variation and evolution. Here we report the finished sequence and biological annotation of human chromosome 1. Chromosome 1 is gene-dense, with 3,141 genes and 991 pseudogenes, and many coding sequences overlap. Rearrangements and mutations of chromosome 1 are prevalent in cancer and many other diseases. Patterns of sequence variation reveal signals of recent selection in specific genes that may contribute to human fitness, and also in regions where no function is evident. Fine-scale recombination occurs in hotspots of varying intensity along the sequence, and is enriched near genes. These and other studies of human biology and disease encoded within chromosome 1 are made possible with the highly accurate annotated sequence, as part of the completed set of chromosome sequences that comprise the reference human genome.

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