三善 陽子

Skeletal dysplasia is a disorder of skeletal development characterized by abnormality in shape, length, a number and mineral density of the bone. Skeletal dysplasia is often associated with manifestation of other organs such as lung, brain and sensory systems. Skeletal dysplasias or dysostosis are classified with more than 400 different names. Enchondral bone formation is a coordinated event of chondrocyte proliferation, differentiation and exchange of terminally maturated chondrocyte with bone. Impaired enchondral bone formation will lead to skeletal dysplasia, especially associated with short long bones. Appropriate bone volume and mineral density are achieved by balance of bone formation and bone resorption and mineralization. The gene encoding fibroblast growth factor receptor 3 is responsible for achondroplasia, representative skeletal dysplasia with short stature. The treatment with growth hormone is approved for achondroplasia in Japan. Osteogenesis imperfecta is characterized by low bone mineral density and fragile bone. Data on the beneficial effect of bisphosphonate for osteogenesis imperfecta are accumulating. Osteopetrosis has high bone mineral density, but sometimes show bone fragility. In Japan as well as other countries, pediatrician treat larger numbers of patients with skeletal dysplasia with short stature and fragile bones compared to 20 years ago.

Aim: Hepatic steatosis accompanied by impaired protein synthesis is often observed in hepatic dysfunction. To assess whether protein synthesis inhibition directly induces hepatic steatosis, we investigated the molecular mechanisms of cycloheximide (CHX)-induced fatty liver mice. Methods: C57/BL6CR mice were i.p. administrated CHX (20 mg/kg) three times every 4 h to induce hepatic steatosis. Hepatic lipid secretion, fatty acid oxidation, hepatic lipogenesis and hepatic lipid uptake were evaluated. Results: Twenty-four hours after the first CHX injection, hepatic lipid levels increased in CHX-treated mice to 1.8-fold of that in controls but returned to normal within 48 h. The hepatic triglyceride (TG) secretion rate decreased significantly to 22% of controls, and the apolipoprotein B (apoB) protein level, but not microsomal TG transfer protein, decreased in CHX-treated mice. The apob gene expression was not significantly different between controls and CHX-treated mice. On the other hand, plasma free fatty acid and lipogenic protein levels did not increase and plasma beta-hydroxybutyrate level remained stable, suggesting that the coordinated balance between fatty acid oxidation, hepatic lipid uptake and lipogenesis was not disrupted in this model. Cellular lipid accumulation and decreased cellular and secreted apoB were also observed in CHX-treated HepG2 cells. Knockdown of apoB in HepG2 cells also resulted in the cellular TG accumulation. Conclusion: We demonstrated that decreased hepatic lipid secretion due to acute apoB reduction is involved in the pathogenesis of CHX-induced liver steatosis.

X-linked adrenoleukodystrophy (X-ALD) is a genetic disease associated with demyelination of the central nervous system, adrenocortical insufficiency and accumulation of very long chain fatty acids. It is a clinically heterogeneous disorder ranging from a severe childhood cerebral form to an asymptomatic form. The incidence in Japan is estimated to be between 1:30,000 and 1:50,000 boys as determined by a nationwide retrospective survey between 1990 and 1999, which found no cases with Addison's form. We reviewed the medical records of eleven Japanese boys with X-ALD from 1990 to 2010 in our institute. Eight patients were detected by neuropsychological abnormalities, whereas a higher prevalence of unrecognized adrenocortical insufficiency (5/11: 45%) was observed than previously recognized. While no neurological abnormalities were demonstrated in two brothers, the elder brother had moderate Addison's disease at diagnosis and the presymptomatic younger brother progressed to Addison's disease six months after the diagnosis of X-ALD. Early detection of impaired adrenal function as well as early identification of neurologically presymptomatic patients by genetic analysis is essential for better prognosis. Addison's form might be overlooked in Japan; therefore, X-ALD should be suspected in patients with adrenocortical insufficiency.

Infantile hepatic hemangioma with consumptive hypothyroidism is a rare condition. A 4-month-old girl presented with diffuse hepatic hemangiomas during treatment of congenital hypothyroidism. Serum reverse triiodothyronine was elevated, and her hypothyroidism improved concomitant with involution of the hemangioma following prednisolone and interferon-alpha administration. At 20 months of age, 7 months after discontinuing prednisolone and interferon-alpha, a focal hemangioma regrew from one of the previous lesions and was surgically resected. The expression and activity of type 3 iodothyronine deiodinase (D3) were elevated in the resected tumor tissue compared with placenta. Here, we describe a patient with consumptive hypothyroidism and diffuse infantile hepatic hemangiomas, one of which regrew after involution following pharmacotherapy. The etiology of elevated D3 activity is also discussed. It is important to identify infantile hepatic hemangioma in patients with hypothyroidism refractory to hormone replacement therapy, who have low free triiodothyronine despite high thyrotropin and normal free thyroxine levels, and long-term follow-up will be needed for these patients.

Glycosylation is one of the most common posttranslational modification reactions and nearly half of all known proteins in eukaryotes are glycosylated. In fact, changes in oligosaccharides structures are associated with many physiological and pathological events, including cell growth, migration and differentiation, and tumor invasion. Therefore, functional glycomics, which is a comprehensive study of the structures and functions of glycans, is attracting the increasing attention of scientists in various fields of life science. In cases of thyroid cancer, the biological characters and prognosis are completely different in each type of histopathology, and their oligosaccharide structures as well as the expression of glycosyltransferases are also different. In this review, we summarized our previous papers on oligosaccharides and thyroid cancers and discussed a possible function of oligosaccharides in the carcinogenesis in thyroid cancer. Copyright © 2010 Eiji Miyoshi et al.

We present a 6-year-old boy with a virilizing adrenocortical tumor who initially presented with peripheral precocious puberty. Development of facial acne, pubic hair and a growth spurt were noted at the age of five. A low-pitched voice as well as maturation of external genitalia was noted at the age of six. Both serum and urinary levels of adrenal androgens were elevated. Abdominal computed tomography revealed a large right suprarenal mass and he underwent surgical resection without any complications. The histological diagnosis was adrenocortical carcinoma according to the criteria of Weiss. Following surgical removal of the androgen-producing tumor, the patient subsequently developed hypothalamic-pituitary activation and demonstrated central precocious puberty. He was treated with a gonadotropin-releasing hormone agonist in order to delay further pubertal progression. Clinical follow-up of potential secondary effects of excess hormone secretion after removal is important in some pediatric patients with virilizing adrenocortical tumor.

We report a male infant with FATCO syndrome, an acronym for fibular aplasia, tibial campomelia, and oligosyndactyly. Courtens et al. reported an infant with oligosyndactyly of the left hand, complete absence of the right fibula, bowing of the right tibia, and absence of the right fifth metatarsal and phalanges. They noted 5 patients with similar clinical features, and proposed the FATCO syndrome. Our patient had a left-sided cleft lip, cleft palate, oligosyndactyly of the right hand and bilateral feet, and bilateral anterior bowing of the limbs associated with overlying skin dimpling. Radiographs showed a short angulated tibia with left fibular aplasia and right fibular hypoplasia. We consider our case the 6th patient with FATCO syndrome, and the cleft lip and palate, not reported in the previous 5 patients, may allow us to further understand the development of the extremities and facies.

With recent improvements in the diagnosis and treatment of cancer, the number of childhood cancer survivors (CCSs) has been increasing in Japan. The importance of quality of life during the lifetime of CCSs has now been recognized, and the late effects of cancer treatments are essential and important issues. In this study we analyzed the endocrinological abnormalities of CCSs by retrospectively evaluating 122 outpatients (62 males and 60 females) who had been referred From pediatric oncologists 10 Our follow-up clinic among 151 CCSs attending our hospital more than two years after their cancer treatment. Follow-up duration varied from 2 to 30 (median 8.0) years. Their average age was 17.3 (range 4-36, median 17.0) years, and 38 patients (31.1%) reached adulthood. Endocrinological abnormalities were found in 82 (67%) of 122 survivors. Gonadal dysfunction was observed in 60 patients (49%). Thirty-nine patients (32%) were short or grew at a slower rate. Twenty-six patients (21%) showed thyroid dysfunction. Other abnormalities were as flollows: obesity in 20 patients (16%), leanness in 10 (8%), central diabetes insipidus in 11 (9%) and adrenocortical dysfunction in 9 (7%). Low bone mineral density was observed in 41 (42%) of 98 patients evaluated. These endocrinological abnormalities were caused by the combined effects of cancer itself and various treatments (chemotherapy, radiation therapy, surgery, and hematopoietic stem cell transplantation). Lifetime medical surveillance and continuous follow-Up are necessary for CCSs, because treatment-related complications may occur during childhood and many years after the therapy as well. Endocrinologists should participate in long-term follow-up Of these survivors ill collaboration with pediatric oncologists.

Silver-Russell syndrome (SRS) is characterized by growth failure and dysmorphic features and is frequently caused by hypomethylation (epimutation) of the H19-DMR. Although molecular and clinical studies have extensively been performed for SRS patients themselves, such studies have not been carried out for placentas. We identified 20 epimutation-positive and 40 epimutation-negative Japanese SRS patients and obtained placental weight data from 12 epimutation-positive and ten epimutation-negative patients and paraffin-embedded placental tissues for molecular and histological examinations from three epimutation-positive and two epimutation-negative patients. Methylation patterns were comparable between leukocytes and placentas in both epimutation-positive and epimutation-negative patients. Epimutations resulted in virtually no IGF2 expression and biallelic slight H19 expression in the leukocytes and obviously reduced IGF2 expression of paternal origin and nearly normal H19 expression of maternal origin in the placentas. Epimutation-positive patients had characteristic body phenotype and small placentas with hypoplastic chorionic villi, and epimutation-negative patients had somewhat small placentas with hypoplastic chorionic villi or massive infarction. Furthermore, significant correlations were identified between the H19-DMR methylation index and the body and placental sizes and between the placental weight and the body size in the epimutation-positive patients, whereas such correlations were not detected for the head circumference. These results suggest (1) characteristic phenotype and reduced IGF2 expression in the epimutation-positive placentas; (2) similarities and differences in the epigenetic control of the IGF2-H19 domain between leukocytes and placentas; (3) a positive role of the IGF2 expression level, as reflected by the methylation index, in the determination of body and placental growth in epimutation-positive patients, except for the brain where IGF2 is expressed biallelically; (4) involvement of placental dysfunction in prenatal growth failure; and (5) relevance of both (epi)genetic factor(s) and environmental factor(s) to SRS in epimutation-negative patients.

Thyroid hormones are known to be essential for growth, development, and metabolism. Recently, the monocarboxylate transporter 8 (MCT8) was identified as a thyroid hormone transporter, and MCT8 mutations have been associated with Allan-Herndon-Dudley syndrome, an X linked condition characterized by severe mental retardation, dysarthria, athetoid movements, muscle hypoplasia, and spastic paraplegia. Here we describe in detail the clinical and biochemical features and the response to thyroid hormone (L-thyroxine (LT4)) administration in a boy with an MCT8 mutation (c.1649delA) that truncates the protein in the twelfth transmembrane domain. It is of note that brain magnetic resonance imaging (MRI) revealed delayed myelination from infancy. Endocrine functions other than thyroid hormone regulation and metabolism were intact, resulting in normal hypothalamic/pituitary function tests. While LT4 administration suppressed thyrotropin (TSH) secretion, no significant changes in thyroid hormone values or clinical symptoms were observed. Conclusion: the characteristic thyroid hormone function tests and brain MRI findings may allow screening of high-risk populations for a better understanding of MCT8 pathophysiology.

Mandibuloacral dysplasia (MAD) is a rare autosomal recessive progeroid syndrome, characterized by mandibular hypoplasia, acroosteolysis affecting distal phalanges and clavicles, delayed closure of the cranial sutures, atrophic skin, and lipodystrophy. Recently, mutations in lamin A/C (LMNA) and zinc metalloprotease (ZMPSTE24), involved in post-translational processing of prelamin A to mature lamin A, have been identified in MAD kindreds. We now report novel compound heterozygous mutations in exon 1 (c.121C > T; p.Q41X) and exon 6 (c.743C > T; p.P248L) in ZMPSTE24 in two Japanese sisters, 7- and 3-year old, with severe MAD and characteristic facies and atrophic skin. The older sister had lipodystrophy affecting the chest and thighs but sparing abdomen. Their parents and a brother, who were healthy, had heterozygous mutations. The missense mutation, P248L, was not found in 100 normal subjects of Japanese origin. The mutant Q41X was inactive in a yeast halo assay; however, the mutant P248L retained near normal ZMPSTE24 activity. Immunoblots demonstrated accumulation of prelamin A in the patients' cell lysates from lymphoblasts. The lymphoblasts from the patients also revealed less intense staining for lamin A/C on immunofluorescence. We conclude that ZMPSTE24 deficiency results in accumulation of farnesylated prelamin A, which may be responsible for cellular toxicity and the MAD phenotype.

Backgound: The clinical features of hepatitis C virus (HCV)-associated liver diseases, or the efficacy of interferon (IFN) therapy in children with Down syndrome (DS) remain to be elucidated. The purpose of the present paper was to survey the features of liver diseases in this subset of children and evaluate the efficacy of IFN treatment in those patients. Methods: A questionnaire was sent to 41 members of the Japan Society of Pediatric Hepatology. Ten of them reported on 11 patients with DS who had concomitant chronic HCV infection, providing information on liver disease and the response to IFN treatment. Results: Interferon therapy of 24 weeks duration using natural IFN-alpha was instituted in six of the 11 patients with DS, but none of the six patients cleared HCV-RNA from their serum. Among 12 age- and sex-matched control children who were treated with IFN using the same regimen against chronic HCV infection, half of them had a favorable response to IFN therapy with a sustained clearance of HCV-RNA from their serum. The major baseline features including alanine aminotransferase levels, HCV genotype and viral load were not apparently different between the six patients with DS and the 12 controls. Conclusions: IFN therapy for HCV infection in patients with DS may be unfavorable as compared with non-DS children.

小児腫瘍性疾患の治療終了後2年以上経過した108名(男52名・女56名・平均17.2歳)を対象に晩期障害を調べた。原疾患の内訳は血液腫瘍58名、脳腫瘍25名、固形腫瘍25名で、治療内容は化学療法102名、外科的治療52名、放射線療法65名、移植56名であった。晩期障害としては、性腺機能低下症57名、成長障害37名、甲状腺機能低下症26名、肥満21名、中枢性尿崩症10名、副腎皮質機能低下症9名を認めた。ホルモン補充療法が行われていたのは、成長ホルモン13名、性腺補充療法26名、甲状腺ホルモン21名、副腎皮質ステロイド9名、DDAVP点鼻10名であった。成長障害の原因は、成長ホルモン分泌不全性低身長症以外に、原疾患の治療中に生じた成長障害からcatch upできていない患者、脊椎へ放射線照射を受けた患者、思春期年齢に原疾患の治療が重なった患者など、様々な要因があった。内分泌学的問題点の他にも、脳腫瘍治療後患者を中心に多くの問題点を認めた。

Persistent hyperinsulinemic hypoglycemia of infancy (PHHI) is often resistant to medical therapy and is normally treated by subtotal pancreatectomy to avoid neurological complications. However, many problems after surgery, such as recurrence of hypoglycemia and diabetes mellitus, remain to be solved. This report concerns a case of PHHI that was resistant to octreotide or diazoxide alone but was successfully controlled with subcutaneous injection of octreotide in combination with nocturnal glucose infusion through central venous catheter. The patient exhibited natural remission of hyperinsulinism with age, and all treatment was ceased at the age of 4 yr. Growth and neurological development of the patient have been normal. This combined therapy can be a therapeutic option as a substitute for surgical solutions. Copyright© 2007 by The Japanese Society for Pediatric Endocrinology.

Frasier syndrome is characterized by slowly progressive nephropathy, male pseudohermaphroditism, streak gonad, and high risk of gonadoblastoma development. Here we report a case of a 46,XY phenotypic female with Frasier syndrome, who was under hemodialysis. While her serum estradiol level was gradually increasing annually, gonadotropin level was constantly extremely high, and her appearance was still prepubertal. She was heterozygous for a novel guanine > adenine point mutation at position +1 of the splice donor site within intron 9 (IVS 9 + 1G > A) of the Wilms' tumor 1 gene. The possibility of this disease should be taken into consideration whenever we encounter a patient with steroid-resistant nephrotic syndrome and delayed puberty.

Recently, the reemergence of vitamin D deficiency in developed countries has been pointed out. Vitamin D deficiency is diagnosed based on the serum 25-hydroxyvitamin D (25OHD) level. However, its normal range is still controversial, making the diagnosis of vitamin D deficiency difficult. Here, we present seven Japanese patients diagnosed with vitamin D deficiency. Three patients complained of leg bowing, and the other four of tetany. The patients with leg bowing were toddlers. Radiographic surveys demonstrated evidence of rickets. Laboratory findings showed decreased levels of serum inorganic phosphorus and increased levels of alkaline phosphatase (ALP) and intact-parathyroid hormone (iPTH). The serum levels of 25OHD were relatively low, ranging from 13 to 15.2 ng/ml. Of the patients with tetany, three were young infants. Laboratory findings showed decreased levels of serum calcium and increased levels of ALP and iPTH. The serum levels of 25OHD were markedly decreased (below 8 ng/ml). Thus, these results indicate that relatively low levels of 25OHD can cause rickets, a symptom of vitamin D deficiency, and that clinicians should therefore carefully evaluate the levels of 25OHD.

Haploinsufficiency of the short stature homeobox-containing (SHOX) gene causes Turner skeletal features, a certain proportion of idiopathic short stature and Leri-Weill dyschondrosteosis (LWD). Here we report a Japanese female with LWD. Her physical growth, skeletal deformity, and endocrine status were recorded longitudinally. She exhibited a constant growth rate (average + 6.2 cm/yr) from 6 to 9 yr old, followed by a downward shift at 10 yr old. Her final height was 135 cm (-4.4 SD for an adult female) and weight was 50.5 kg (-0.3 SD) at 12 yr and 10 mo old. Mesomelia and cubitus valgus were noticed from 2 yr old, and metaphyseal lucency and epiphyseal hypoplasia of the medial side of the distal radius were detected at 6 yr old. Madelung deformity was obvious at 10 yr old, when menarche occurred. Fluorescence in situ hybridization (FISH) analysis demonstrated a single copy of the SHOX gene. The short stature of the patient was thought to be exaggerated by the combination of SHOX haploinsufficiency and relatively early puberty. Copyright© 2005 by The Japanese Society for Pediatric Endocrinology.

Although gonadal estrogens are known to facilitate the development of skeletal lesion in SHOX haploinsufficiency, controversy exists as to whether gonadal estrogens are disadvantageous to pubertal growth. To clarify this matter, we analyzed growth pattern in 31 Japanese patients with a normal karyotype and molecularly confirmed SHOX haploinsufficiency. The mean height SD score at the diagnosis of SHOX haploinsufficiency was similar between patients identified in childhood and those identified in adulthood (-2.7 +/- 0.8 [n = 15] vs. -2.4 +/- 0.7 [n 16], P = 0.36), and was significantly lower in patients identified by the studies for short stature than in those ascertained by the familial studies of the probands both in childhood (-3.0 +/- 0.6 [n = 11] vs. -1.8 +/- 0.5 [n = 4], P = 0.0051) and in adulthood (-3.0 +/- 0.9 [n = 5] vs. -2.2 +/- 0.5 [n = I I], P = 0.040). Analysis of longitudinal paired growth data obtained in seven females showed a significantly different mean height SD score between childhood and adulthood (-2.3 +/- 0.5 vs. -2.9 +/- 0.8, P = 0.0060). The results imply that gonadal estrogens have a deleterious effect on pubertal growth in SHOX haploinsufficiency, and that the growth disadvantage is recognizable by longitudinal rather than cross-sectional growth studies.

We report a case of Japanese girl with a rare disorder of Weaver syndrome, which was characterized by overgrowth with advanced and disharmonic bone age, craniofacial abnormalities, developmental delay, metaphyseal flaring of the long bones and camptodactyly. The patient was delivered at 38 weeks of gestation with a length of 54.2 cm (+ 2.6 SD), a weight of 3805 g (+ 2.5 SD) and an occipitofrontal circumference (OFC) of 35.0 cm (+ 1.1 SD). She manifested hypertonia and flexion contractures in the first few years. She also had submucosal soft cleft palate and difficulty in swallowing and breathing in early infancy. When she was 5 years and 7 months old, her height and weight were 133.3 cm (+ 5.5 SD) and 32.0 kg (+ 5.1 SD), respectively. We could not detect any endocrinological abnormalities for the cause of overgrowth. According to clinical features, Weaver syndrome was suspected and genetical analysis was performed. Fluorescence in situ hybridization (FISH) and direct sequencing analysis showed neither deletion nor point mutation of the nuclear receptor SET-domain-containing protein 1 (NSD1) gene on 5q35, which is responsible for Sotos syndrome. Therefore, we made a diagnosis of Weaver syndrome for this patient and discussed the differential diagnosis in terms of overgrowth syndrome. Copyright© 2004 by The Japanese Society for Pediatric Endocrinology.

The ossification of the skeleton progresses in a predictable sequence in the fetus and children, allowing us to evaluate skeletal maturation by comparison with normal agerelated standards. An atlas, which describes the pattern of the ossification sequence mainly in the left hand and wrist, is available in children to estimate skeletal maturation, or bone age. Because of the difference in the ossification progression of skeletal maturation according to race and sex, we have to refer to an adequate atlas of standards. The standards of Greulich and Pyle are divided by sex but were developed in American white children. The standards of Tanner and Whitehouse adopted a scoring system for each individual bone in the left hand and were developed in British children. Now we have Japanese standards in a radiographic atlas of skeletal maturation. The assessment of bone age and the comparison of it with chronological age and actual height are very important for making differential diagnoses in patients with short stature.

Sotos syndrome is an overgrowth syndrome, which is characterized by pre- and postnatal overgrowth in childhood that usually normalizes by adulthood, characteristic face, macrocephaly, advanced bone age and developmental delay. Here we reported an adult case of Sotos syndrome, who reached final height. The diagnosis was confirmed by the deletion of the NSD1 gene. Although the growth of the patient was rapid in the first three years, his final height was within the normal range.

Background/Aims: Thrombospondin-1 is a major activator of transforming growth factor-beta1 (TGF-beta1), and a peptide derived from the latency-associated peptide, Leu-Ser-Lys-Leu (LSKL), inhibits the activation of TGF-beta1. In this study, the effects of LSKL on the hepatocyte damage and fibrogenesis in dimethylnitrosamine (DMN)-induced rat liver fibrosis were examined. Methods: Animals were given an intraperitoneal (i.p.) injection of DMN or saline three times per week for 4 weeks, and treated with LSKL, a control peptide, or saline i.p. daily. Results: Liver atrophy caused by DMN-injection was significantly inhibited in the DMN + LSKL group. The degrees of necrosis/degeneration and fibrosis scores were significantly lower in the DMN + LSKL group than in the control groups. The hydroxyproline content was significantly higher in the control groups than in the DMN + LSKL group. The amount of active TGF-beta1 was less in the DMN + LSKL group than in the control groups, and the active/total TGF-beta1 ratio in the DMN + LSKL group was suppressed in the control groups. Phosphorylation of Smad 2 in the liver was significantly decreased in the DMN + LSKL group. Conclusions: The LSKL peptide prevented the progression of hepatic damage and fibrosis through the inhibition of TGF-beta1 activation and its signal transduction in vivo. (C) 2003 European Association for the Study of the Liver. Published by Elsevier B.V. All rights reserved.

Sotos syndrome (SoS) is an autosomal dominant overgrowth syndrome with characteristic craniofacial dysmorphic features and various degrees of mental retardation. We previously showed that haploinsufficiency of the NSD1 gene is the major cause of SoS, and submicroscopic deletions at 5q35, including NSD1, were found in about a half (20/42) of our patients examined. Since the first report, an additional 70 SoS cases consisting of 53 Japanese and 17 non-Japanese have been analyzed. We found 50 microdeletions (45%) and 16 point mutations (14%) among all the 112 cases. A large difference in the frequency of microdeletions between Japanese and non Japanese patients was noted: 49 (52%) of the 95 Japanese patients and only one (6%) of the 17 non-Japanese had microdeletions. A sequence-based physical map was constructed to characterize the microdeletions. Most of the microdeletions were confirmed to be identical by FISH analysis. We identified highly homologous sequences, i.e., possible low copy repeats (LCRs), in regions flanking proximal and distal. breakpoints of the common deletion. This suggests that LCRs may mediate the deletion. Such LCRs seem to be present in different populations. Thus the different frequency of microdeletions between Japanese and non, Japanese cases in our study may have been caused by patient-selection bias. (C) 2003 Wiley-Liss, Inc.

Sotos syndrome (SoS) is characterized by pre- and postnatal overgrowth with advanced bone age; a dysmorphic face with macrocephaly and pointed chin; large hands and feet; mental retardation; and possible susceptibility to tumors. It has been shown that the major cause of SoS is haploinsufficiency of the NSD1 gene at 5q35, because the majority of patients had either a common microdeletion including NSD1 or a truncated type of point mutation in NSD1. In the present study, we traced the parental origin of the microdeletions in 26 patients with SoS by the use of 16 microsatellite markers at or flanking the commonly deleted region. Deletions in 18 of the 20 informative cases occurred in the paternally derived chromosome 5, whereas those in the maternally derived chromosome were found in only two cases. Haplotyping analysis of the marker loci revealed that the paternal deletion in five of seven informative cases and the maternal deletion in one case arose through an intrachromosomal rearrangement, and two other cases of the paternal deletion involved an interchromosomal event, suggesting that the common microdeletion observed in SoS did not occur through a uniform mechanism but preferentially arose prezygotically.

Background Mother-to-infant transmission of hepatitis C virus (HCV) could become the main route of HCV infection in the future because there are no methods available to prevent vertical infection. The aim of this study was to determine the incidence of mother-to-infant transmission in infants born to mothers who tested positive for anti-HCV antibodies and to elucidate associated risk factors for transmission. Methods. Screening was conducted for 16 800 pregnant women with an anti-HCV antibodies test, and 154 mothers were positive. From the positive group 141 mothers were enrolled in the study and their 147 infants mere followed from birth for serum alanine aminotransferase activity, anti-HCV antibodies and HCV RNA. HIV infection was tested in 73 of 141 mothers, all of whom were negative. Results. Thirty-three infants were dropped from the study because they were followed for <6 months or were not tested adequately. Of the 114 infants finally evaluated 9 (7.8%) had detectable HCV RNA. The transmission rate was not influenced by the mode of delivery [vaginal delivery, 8 of 90 cs. cesarean section, 1 of 24 (P = 0.396)] or by the type of feeding [9 of 98 for breast-fed infants vs. 0 of 16 for formula-fed infants (P = 0.243)]. All infected infants were born to mothers who had HCV viremia at the delivery (P = 0.040) and to those with a high viral load (P = 0.019). Conclusions. Our prospective study showed that the transmission rate of mother-to-infant HCV infection was 7.8% in anti-HCV antibody-positive mothers. Risk was related to the presence of maternal HCV viremia at delivery and a high viral load in the mothers.