Therapeutic Efficacy Of GnRHa In Idiopathic Central Precocious Puberty And Early Puberty Girls And The Relationship Between Idiopathic Central Precocious Puberty Girls And MKRN3 Gene

Objective:To investigate the effect of gonadotropin releasing hormone analog(GnRHa)on idiopathic central precocious puberty(ICPP)and early puberty(EP)girls and the relationship between MKRN3 gene and ICPP girl.Methods:We retrospectively analysed 66 girls aged 5-9.8 years old,with a mean age of 8.1±1.0 years,in the General Hospital of Tianjin Medical University from January 2015 to January 2017.They were diagnosed with ICPP or EP,treated with GnRHa,followed up until the end of treatment.Clinical data:chronological age(CA),bone age(BA),height,weight,body mass index(BMI),bone age index(BAI),predict adult height(PAH),target height(TH),luteinizing hormone(LH),follicle stimulating hormone(FSH),pelvic ultrasound were measured at the beginning of treatment,12 months,at the end of treatment,some patients were followed up to the final height.Using SPSS 22.0,the data of ICPP group and EP group were tested by t-test.ANOVA was used to compare the data before and after treatment with ICPP group and EP group respectively.P<0.05 showed statistical difference.Blood samples were collected from 30 patients diagnosed with ICPP,whole blood genomic DNA was extracted and the subject's MKRN3 gene was sequenced by polymerase chain reaction and direct sequencing.Results:1.BAI in EP group before treatment was higher than that in ICPP group,indicating that the bone age of EP group was significantly earlier than that of ICPP group(P=0.021).At the end of treatment,although BAI in EP group was higher than that in ICPP group,the difference was not statistically significant(P=0.304),indicating a narrowing of the difference between the two groups in terms of bone age and chronological age.2.The BMI in ICPP group and EP group after 12 months of treatment and at theend of treatment were increased than those before treatment,but the difference was not statistically significant(all P>0.05).3.PAH in ICPP group and EP group after 12 months of treatment and at the end of treatment were all higher than those before treatment(all P<0.05).4.The levels of gonadotrophin in ICPP group and EP group after 12 months of treatment and at the end of treatment were significantly lower than those before treatment(all P<0.05).5.The length of the uterus,the volume of the ovary,the diameter of the largest follicle and the number of the follicles larger than 4mm in ICPP group and EP group after 12 months treatment and at the end of treatment were significantly lower than those before treatment(all P<0.05).6.A new missense mutation(c.917G> A,p.Gly360Asp)was found in ICPP girls screening by direct gene sequencing and it also existed in the father of this child.Conclusions:1.MKRN3 gene mutation may be one of the reasons for idiopathic central precocious puberty.2.GnRHa is effective in the treatment of earlier puberty girls.3.GnRHa can improve the height of earlier puberty girls.The appropriate therapeutic dose of GnRHa can control gonadal development and gonadotropin levels and delay bone maturation.