18 | NewScientist | 20 April 2019A GENE that influences how
much alcohol we drink may
also shape our decisions when
choosing a partner.
It is no secret that many couples
have similar patterns when it
comes to alcohol use, but pinning
down the underlying reason has
been tricky.
Laurence Howe at the
University of Bristol, UK, and his
colleagues analysed the geneticdata of 47,000 couples in the UK
Biobank and compared this with
each person’s reported alcohol
consumption. In particular, they
were interested in a variant of the
ADH1B gene, which is known to be
associated with heavier drinking.
They found that regular
drinkers were more likely to pair
up with people who drank similar
amounts, and that each person in
such a pair was more likely to havethis gene variant. People who
didn’t drink very often tended
to form relationships with other
light drinkers, and were more
likely to have a different variant
of the same gene – one associated
with unpleasant alcohol side
effects (bioRxiv, doi.org/c4d6).
“This suggests that alcohol
consumption directly influences
mate choice,” says Howe.
However, the gene is also
linked to socioeconomic status,
so other factors may be at play.PA
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He ain’t weightless,
he’s my brotherNASA astronaut Scott Kelly (above, left) spent a year in
space and came back a slightly changed man – at least,
in comparison to his twin brother Mark (right), who was
earthbound while Scott was aboard the International
Space Station between March 2015 and March 2016.
Scott and Mark (himself a former astronaut) both
gave NASA scientists samples of their blood, urine and
faeces before, during and after the year-long flight.
Scott’s DNA saw some changes, compared to his
twin. His telomeres – the end caps of chromosomes
that usually shorten as we age – lengthened over the340 days he spent in space. This could be due to
exposure to space radiation. Within two days of returning
to Earth, his telomeres rapidly shortened and returned to
their pre-flight length within months.
One big difference between the twins was seen
in their urine. Their metabolites – the products of
metabolic processes – were similar in their blood plasma,
but 32 urinary metabolites were significantly altered
during spaceflight.
On the other hand, their faecal samples retained
similar microbial communities – both dominated by
bacteria from the Firmicutes and Bacteroidetes phyla.
Mark’s faecal microbiome varied more than Scott’s from
pre- to post-flight, but the changes weren’t significant
(Science, DOI: 10.1126/science.aau8650).The ‘drink’ gene that plays cupid
Salmonella hijack
our immune cellsSALMONELLA bacteria can use
immune cells as vehicles to
spread around the body and
they seem to do it by disrupting
electrical signals in the gut.
Usually, the immune system
is good at limiting a salmonella
infection to the gut. But the
bacteria sometimes escape to
other organs like the liver by
riding inside immune cells
called macrophages.
Our intestines have small
electric fields, caused by charged
ions passing in and out of cells.
When Yaohui Sun at the
University of California, Davis,
and his colleagues placed gut
membrane cells from mice in an
electric field, they found that after
engulfing salmonella bacteria,
macrophages moved towards
a negative charge.
In the gut this corresponds to
them leaving the intestines, giving
a ride to any bacteria residing
inside (PLoS Biology, doi.org/c4d9).Plastic hitches a
ride with the windMICROPLASTICS can travel
kilometres through the air.
Deonie Allen and Steve Allen,
both linked to the research centre
EcoLab in France, and colleagues
found microplastics in a remote
area of the Pyrenees mountains.
The local population is small,
suggesting that particles must
have been transported in the air
from more populous areas at
least 95 kilometres away.
Sampling the area over five
months, the team calculated that
the microplastics were depositing
at a rate of 365 particles per square
metre per day (Nature Geoscience,
DOI: 10.1038/s41561-019-0335-5).
While the exact sources of
these particles were unknown, the
likely culprit is single-use plastic
packaging, says Steve Allen.IN BRIEF