TITLE:
Genetic analysis of the human hair roots as a tool for spaceflight experiments
AUTHORS:
Masahiro Terada, Masaya Seki, Akira Higashibata, Shin Yamada, Rika Takahashi, Hideyuki J. Majima, Takashi Yamazaki, Tomomi Watanabe-Asaka, Maki Niihori, Chiaki Mukai, Noriaki Ishioka
KEYWORDS:
Hair Root; Microarray; Space; Astronaut; RNA; Gene Expression
JOURNAL NAME:
Advances in Bioscience and Biotechnology,
Vol.4 No.10B,
October
17,
2013
ABSTRACT: The use of hair roots as experimental samples has
been a research focus for understanding the effects of spaceflight on
astronauts, because it has many advantages, one of which is the fact that
hair matrix cells actively divide in a hair follicle and sensitively reflect
the physical conditions of the human body. In 2009, a research program focusing
on the analysis of astronauts’ hairs was initiated to examine the effects of
long-term spaceflight on the gene expression and mineral metabolism in the
human body. Since the number of samples per astronaut is limited to 5 strands
of hairs at each sampling point, due to the ethical viewpoint of astronauts
or limited resources in space, it is important to develop an effective method
for the molecular analysis of small amounts of hair roots. In this study,
mRNA successfully extracted from 1, 5, and 10 hair follicles was amplified and
subjected to the DNA microarray analysis to compare the gene expression within
subjects. The results indicated that (1) it was possible to perform the genetic
analysis on hair samples stored at -80℃, even without a fixation buffer and
(2) the newly modified method of mRNA extraction and analysis was effective
in detecting differential gene expression
in samples containing only 5 hairs. In conclusion, RNA was efficiently
extracted from 5 hair roots, which is the same number of hair roots used in
the space experiment; therefore, this method can be applied to genetically
analyze astronauts’ hair samples.