Reference : New Scientist, 19 April, page 36
Modern thinking is that the first life was based on RNA. However, experimental work fails to confirm this, because forming RNA in the laboratory, in a way that simulates early conditions on Earth, is next to impossible. An alternate explanation might be that RNA formed in another liquid. A suggested candidate is formamide, which would form from the reaction between hydrogen cyanide and water, both of which would be present in the early atrmosphere.
Imagine a pool of formamide. If hot, it would be water free, since formamide evaporates at a much higher temperature than water. Laboratory experiments show that, in the presence of borates, and in formamide solution, RNA forms much more easily than in water. Borates are common in some geothermal sites, which provide the high temperature needed also.
One complication is that RNA formed in this way would probably dissociate in water. And the early Earth was very wet. This has led some researchers into suggesting that the first RNA based life formed on Mars, where boron is plentiful, and where we now know there was geothermal activity. A large meteor hitting the surface of Mars would send Mars rock as meteorites to Earth.
Still very speculative, but interesting.