Objective: To probe into the correlation between clinical characteristics and vitamin D receptor (VDR) BmsI gene polymorphism in preadolescent children with idiopathic short stature (ISS)

and to analyze the influencing factors of efficacy of recombinant growth hormone (rhGH). Methods: Seventy-two children with ISS admitted into our hospital from Mar. 2016 to Jun. 2018 were extracted as the ISS group

and 60 healthy children participated into the physical examination during the same period were selected as the healthy control group. Clinical data of children were record. BsmI gene polymorphism of two groups was detected by polymerase chain reaction (PCR)

and the theoretical value of each genotype was calculated by the Hardy-Weinberg genetic equilibrium fit test. ISS group was treated with rhGH for more than 1 year

and was divided into BB

Bb and bb genotype according to different genotypes. The growth rate and height standard deviation (Ht-SDS) of children with different genotypes were observed at 3

6 and 12 months after treatment. Pearson was used to analyze the related factors affecting the efficacy of rhGH. Results: There was no significant difference in the age between the healthy control group and the ISS group before treatment (P>0.05). The height

body weight

growth rate

insuline-like growth factor 1(IGF-1)

insuline-like growth factor binding protein-3 (IGFBP-3) of the healthy control group were significantly higher than those of the ISS group (P<0.05). The BB

Bb and bb genotypes of the healthy control group and ISS group were consistent with Hardy-Weinberg genetic equilibrium

and there were statistically significant differences in the frequencies of three genotypes

B and b alleles between two groups (P<0.05). Before treatment

there were no statistically significant difference in birth weight

birth height

height

body weight

height of father

height of mother

actual age and bone age among BB

Bb and bb genotypes (P>0.05). There was no significant difference in growth rate and Ht-SDS among BB

Bb and bb genotypes before treatment and after treatment of 3 months (P>0.05). After treatment of 6 and 12 months

the growth rate and Ht-SDS of three groups increased significantly (P<0.05)

and the change in bb genotype was more significant (P<0.05). Correlation analysis showed that initial treatment age was negatively correlated with △Ht-SDS (changes of Ht-SDS)

and initial IGF-1 and IGFBP-3 levels

BsmI gene polymorphism

initial treatment age

initial growth rate and treatment duration were positively correlated with △Ht-SDS. There was no significant correlation between birth height and body weight

height and body weight before treatment

genetic target height and bone age and △Ht-SDS. Conclusion: BsmI gene polymorphism may be related to ISS pathogenesis and may be the factor affecting the efficacy of rhGH. Meanwhile

the efficacy of rhGH is also affected by IGF-1 and IGFBP-3. The earlier the treatment

the greater the growth rate before treatment

and the longer the course of treatment

the better the treatment effect.