[Breeding and identification of estrogen receptor beta gene knock-out mice].
OBJECTIVE
To breed estrogen receptor beta (ERbeta) gene knock-out female mice for studying postmenopausal osteoporotic fracture.


METHODS
Three pairs of ERbeta gene knock-out mice were bred for 3 months, and 14 2-month-old female wild-type C57BL/6J mice with the same genetic background were paired at the ratio of 2:1 and mated with the male ERbeta gene knock-out homozygote mice. After further breeding to obtain sufficient number of mice, the genome DNA was extracted from the tail of the mice for genotyping by PCR. Ten 4-month-old female filial mice with ERbeta gene knock-out and 10 wild-type female mice were randomly selected and sacrificed, and the right proximal tibiae were removed and subjected to micro CT for measuring the parameters of trabecular bone histomorphometry.


RESULTS
A total of 340 filial generation mice were reproduced in 2 months and genotypic identification revealed a proportion of ERbeta+ or + mice of 23.5%, ERbeta+ or - mice of 48.27 percent; and homozygous mutant (ERbeta- or -) mice of 28.3% (in which 54 were female). The MicroCT data revealed that the micro-architecture of the proximal tibiae was significantly different between ERbeta gene knock-out mice selected from the filial generation and wild type mice (P<0.05).


CONCLUSIONS
It is feasible to breed ERbeta knock-out female mice by introducing female wild-type mice to pair and mate with ERbeta knock-out homozygote male mice. This approach allows breeding of sufficient number of female ERbeta knock-out mice as the animal models for studying the role of ERbeta.
Pan
Xiao-hua
XH
Department of Orthopedics, Second Hospital of Medical College of Ji'nan University, Shenzhen People's Hospital, Shenzhen 518020, China. szpxh4141@163.net
Wang
Yu-gang
YG
Zhang
Ge
G
Liu
Zhong
Z
Zeng
Wan-cheng
WC
Chen
Jia-Kai
JK
Dai
Yong
Y
Qin
Ling
L
D000818:Animals; D001947:Breeding; D004247:DNA / Q000032:analysis; D047629:Estrogen Receptor beta / Q000235:genetics*; D005260:Female; D055786:Gene Knockout Techniques; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout
D047629:Estrogen Receptor beta; D004247:DNA