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About 20 years ago, DNA sequences were separately described from the quagga (a type of zebra) and an ancient Egyptian individual. What made these DNA sequences exceptional was that they were derived from 140- and 2400-year-old specimens. However, ancient DNA research, defined broadly as the retrieval of DNA sequences from museum specimens, archaeological finds, fossil remains, and other unusual sources of DNA, only really became feasible with the advent of techniques for the enzymatic amplification of specific DNA sequences. Today, reports of analyses of specimens hundreds, thousands, and even millions of years old are almost common-place. But can all these results be believed? In this paper, we critically assess the state of ancient DNA research. In particular, we discuss the precautions and criteria necessary to ascertain to the greatest extent possible that results represent authentic ancient DNA sequences. We also highlight some significant results and areas of promising future research. [ABSTRACT FROM AUTHOR]

Relates the history of genetics in France. French biologists and genetics from 1900-1930; Explanation of the delayed development of genetics in France; Experimental and theoretical population genetics; Genetic control of eye pigmentation in Drosophila; Andre Lwoff's physiological evolution and theory of genetic continuity; Distinctiveness of French genetics.

Just as nucleic acids can carry out enzymatic reactions, proteins can be genes. These heritable infectious proteins (prions) follow unique genetic rules that enable their identification: reversible curing, inducible "spontaneous generation," and phenotype surprises. Most prions are based on self-propagating amyloids, depend heavily on chaperones, show strain phenomena and, like other infectious elements, showspecies barriers to transmission. A recently identified prion is based on obligatory self-activation of an enzyme in trans. Although prions can be detrimental, they may also be beneficial to their hosts. [ABSTRACT FROM AUTHOR]

Looks into the molecular aspects of phylogeny. Methods for inferring phylogeny; Possibility of sequencing proteins and nucleic acids; Statistical tests of phylogeny.