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Some potential articles of interest:

This Week in Science
Editor summaries of this week's papers.
Science 10 November 2006: 889.
Highlights of Research in This Issue
Well-Rounded Diet

The diets of early human ancestors have been difficult to
determine. Our
closest common ancestor, the chimpanzee, forages primarily
on fruits and
nuts that come from plants that use the C3 photosynthetic
pathway. Later
hominins, of the genus Homo clearly had a diverse diet that
included animals
feeding on grasses (which use the C4 pathway). It has been
thought that the
development of tools by Homo allowed this diversification in
diet.
Sponheimer et al. (p. 980; see the Perspective by Ambrose)
studied the
carbon isotope signature of enamel layers from teeth of
Paranthropus
robustus. This early hominin switched from a diet rich in C3
plants to one
with a C4 source seasonally. Thus, the extinction of P.
robustus, who
apparently did not use tools, cannot be explained by a
restricted diet.

This Week in Science
Editor summaries of this week's papers.
Science 10 November 2006: 889.
Highlights of Research in This Issue
The Bald Truth About Lipids

Hair loss can be traumatic, whether it is linked to illness
or simply part
of the natural aging process, and there is considerable
interest in
dissecting its underlying mechanisms. Kazantseva et al. (p.
982) identify a
culprit gene in a group of Russian families who show an
inherited deficiency
in hair growth but are otherwise healthy. The mutant gene,
LIPH, encodes
lipase H, a phospholipase thought to regulate the production of
lipid-signaling molecules. This discovery will likely stimulate
investigations aimed at understanding the precise role of
lipase H in hair
follicle biology and whether the LIPH gene also contributes
to the more
common forms of baldness in the general population.

This Week in Science
Editor summaries of this week's papers.
Science 10 November 2006: 889.
Highlights of Research in This IssueToward Defeating
Blindness in the
Elderly

Age-related macular degeneration (AMD) is a common cause of
blindness in the
elderly and is characterized by a breakdown of
light-sensitive cells in the
retina that results in progressive loss of central vision.
The neovascular,
or "wet," form of AMD is especially devastating for patients
because vision
loss is rapid. Studying a Chinese population, DeWan et al.
(p. 989,
published online 19 October) identified a single nucleotide
polymorphism
(SNP) in the HTRA1 gene that confers a greatly increased
risk of developing
wet AMD. The HTRA1 gene, located on chromosome 10q26,
encodes a heat shock
serine protease, and the SNP resides within the gene's
promoter region. Yang
et al. (p. 992, published online 19 October) find that the
same SNP also
increases AMD risk in a Caucasian population and is
associated with higher
expression levels of HTRA1 messenger RNA and protein.
Identification of this
gene may ultimately lead to improved diagnosis and treatment
of AMD (see the
20 October news story by Marx).

Editors' Choice
Highlights of the recent literature.
Science 10 November 2006: 895.
GENETICS: Live Fast, Die Early

How an organism repairs damage to its DNA has important
implications for
disease and, potentially, for aging, as the latter is
correlated with
increasing DNA damage. Double-stranded breaks (DSBs) in DNA
are particularly
noxious, and cells have evolved several ways to cope:
Homologous
recombination (HR) uses the sequences of a homologous
chromosome to patch
the damaged site, which minimizes the chance of mutation,
whereas
nonhomologous end joining (NHEJ) is faster but may introduce
small additions
or deletions.

Preston et al. have looked at the way germ cells in male
Drosophila deal
with DSB damage over the lifetime of the individual. They
find that the
importance of the various pathways changes substantially,
with young
(1-week-old) males showing a low level (~15%) of repair via
HR, which
increases to 60% in 6-week-old flies. On the other hand,
flies that died or
became infertile after only 4 weeks had a tendency to show
increasing
NHEJ-based repair of the DSB with age. The authors speculate
that young
flies might benefit from rapid gamete development and
production (and thus
being first to mate), and therefore evolution favors the
rapidity of NHEJ
repairs, which outweighs the mutational burden. Older flies,
having outlived
most of the competition, might find themselves in an
environment where the
frequency of mating is low and speed is no longer a critical
factor. -- GR

Curr. Biol. 16, 2009 (2006).