Abstract We describe a 15 10/12‐year‐old boy (Tanner stage 4, peak growth velocity 7 cm/year) with a ring X chromosome who presented with extreme short stature (mean ‐ 5.3 SD) as the sole recognizable abnormality. His chromosome constitution was determined to be 46,Y, r(X) (p22.33q28) in 174 of 182 peripheral blood cells and in 35 skin fibroblasts. Of the remaining eight peripheral blood cells, five had a dicentric double‐size ring and three had a smaller ring. Other laboratory studies for short stature were noncontributory. We suspect that the ring's specific behavior in mitosis or its effect on expression of the statural determinant on the X chromosome short arm may be responsible for short stature in this patient.
The purpose of this study is to construct the cross-sectional head circumference growth curves, intended for clinical use, for the Japanese from birth to 18 years of age.Two sets of the national survey data on head circumference and height were utilized for the study: (1) The 1990 data collected by the Japanese Ministry of Health and Welfare on children below 7 years of age (n = 16 621, 8511 males, 8110 females). (2) The 1992-1994 data collected by the Research Institute of Human Engineering for Quality Life on children from 7 to 18 years of age (n = 10 183, 5610 males, 4573 females). We used the LMS method to obtain the 3rd, 10th, 25th, 50th, 75th, 90th and 97th percentile values for each age and gender.The results showed a persistent positive secular trend in head circumference in Japanese children of both genders. Comparison of these data with those of recent Caucasian studies revealed ethnic difference in head circumference, with Japanese having relatively larger head circumference for height as compared with Caucasians.
We report the case of a 2.5-year-old Japanese boy with a new overgrowth syndrome who presented with excessive postnatal growth, mental retardation, unusual facial features, megaepiphyses in the long bones and hypertrophy of the mitral valve. The facial features included a prominent forehead, supraorbital ridges, hypertelorism and a long philtrum. The urine mucopolysaccharides and leucocyte morphology were unremarkable. This pattern did not fit any known overgrowth syndrome.
A 10-year-old Japanese boy with nonendocrine short stature who was treated with GH showed discordant pubertal development and advanced skeletal maturation. GH therapy was started at 6.8 years of age at a dose of 0.5u/kg/week, when his height age was 3.3 years and bone age was 4.8 years. At 10.3 years of age his height and bone age reached 7.5 and 9.0 years, respectively, but unexpectedly he developed pubic hair (Tanner stage II, with a testicular volume of 4mL). It appears that the pharmacological dose of GH prematurely induced Leydig cell activity in this patient.
Abstract Deletion and RFLP studies with 5 cloned DNA markers localized at 15q11.2 were performed in 50 patients with the Prader–Willi syndrome (PWS). A one‐copy density (deletion) for at least one of 4 loci, D15S9, D15S11, D15S10, D15S12 , was detected in 32 (64%) of the 50 patients; deletions of each of the 4 loci were found in 29, 30, 29, and 28 patients, respectively. Three patients showed 4 or more copy density for D15S12 locus, in addition to deletions. The remaining 18 patients showed two‐copy densities for each of the 4 loci. A common site of rearrangements among our 32 patients as well as the reported patients seemed to be confined to a segment between D15S9 and D15S11 , suggesting the putative PWS gene locus in this segment. Of 6 patients who have cytologic deletions but did not show any molecular deletions, 3 have normal size of hands and feet, and 4 have normally pigmented skin and hair. The normal pigmentation was also observed in 3 patients who had small molecular deletions in the examined 5‐locus segment. These observations may support the conception of contiguous gene syndrome. RFLP analysis demonstrated maternal uniparental isodisomy of chromosomes 15 in both a patient with 45,t(15q;15q) and a karyotypically normal patient. Based on the results of the present study, a new model is proposed to explain the occurrence of PWS with a variety of chromosome abnormalities, including partial monosomy, disomy, trisomy, and/or tetrasomy for 15q11.2. The normal development may require an even or more “number ratio” of paternally derived allele(s) to maternally derived allele(s) of the gene(s) localized at 15q11.2, and a disturbance of the ratio would lead to the PWS phenotype.
Large datasets of detailed anthropometric measurements are scarce in children. The Japanese Standard Association 1978-1981 survey provides a rare opportunity to use high quality data from Japanese children.To construct inside leg length (ILL) and inside leg length to stature ratio (ILL/S) reference centile curves for Japanese children.The study sample consisted of 14,825 boys and 14,577 girls age 0-18 years for stature and weight measurements, and 9064 boys and 8796 girls age 0-12 years for ILL measurements, who participated in the 1978-1981 national survey on body sizes. LMS method was used to construct the reference centile curves. The reference centile curves for stature, weight, ILL, and ILL/S were compared to those of British children.The L, M, and S reference values for Japanese children are presented for stature, weight, ILL, and ILL/S. Compared with British children of 0-12 years of age, Japanese children of 0-12 years of age had shorter median stature, shorter median ILL, and shorter median ILL/S.We present the first reference values for ILL and ILL/S in Japanese children. Japanese children had relatively shorter legs compared to British children from infancy.
A patient with an optic glioma who had been treated by radiotherapy developed right thalamic hemorrhage 4 months after starting growth hormone (GH) therapy. This was probably due to the irradiation but the GH therapy may have contributed.
