Study of final height in Turner's syndrome: ethnic and genetic influences

In understanding Turner's syndrome, spontaneous adult height is a prerequisite for an accurate assessment of the therapeutic efficiency of growth hormone treatment. The heights described in the literature reveal significant differences (136–147 cm). Our collaborative study pooled results from 16 pediatrie endocrinology centers and obtained a large number of spontaneous adult heights ( n = 216). The selective criteria were: chronological age (CA) > 18 years, bone age (BA) > 16 years, typical karyotype, no treatment with growth hormone or anabolic steroids. Mean CA was 23.3 ± 5.6 years. Chromosomal anomalies were: monosomy X 56%; mosaicism 37.2%; structural aberration 10.6%. Mean final height in the whole group was 141.5 (129–160) cm. There was no significant difference in height between the three groups: monosomy X( n =121:141.1±6.4 cm); mosaicism ( n = 72: 141.5 ± 7.5 cm); X anomaly ( n = 23: 141.4±5.0 cm). Mean parental height was 170.4 ± 7.1 cm (father) and 160.1 ± 6.2 cm (mother). Parental height and patients' heights correlated significantly, but more so with fathers' heights ( r = 0.50) than with mothers'( r = 0.42). The correlation was still apparent with the target height ( r = 0–55). The results of different series in the literature show the existence of significant variations as mean final heights are between 136 and 147 cm. These differences can be explained by the variations in normal female heights in each country. We have found in these different countries a very strong correlation ( r = 0.9I) between normal height and final height in Turner's syndrome. It is therefore necessary to know the spontaneous final height for Turner's syndrome in different countries in order to judge the efficacy of growth hormone treatment, and also to take into account the target height of each child in order to evaluate individual results.