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Aging is a complex biological process. A study of pyrroline-5-carboxylate reductase 1 (PYCR1) deficiency, which causes a progeroid syndrome, may not only shed light on its genetic contribution to autosomal recessive cutis laxa (ARCL) but also help elucidate the functional mechanisms associated with aging. In this study, we used RNA-Seq technology to examine gene expression changes in primary skin fibroblasts from healthy controls and patients with PYCR1 mutations. Approximately 22 and 32 candidate genes were found to be up- and downregulated, respectively, in fibroblasts from patients. Among the downregulated candidates in fibroblasts with PYCR1 mutations, a strong reduction in the expression of 17 genes (53.1%) which protein products are localized in the extracellular space was detected. These proteins included several important ECM components, periostin (POSTN), elastin (ELN), and decorin (DCN); genetic mutations in these proteins are associated with different phenotypes of aging, such as cutis laxa and joint and dermal manifestations. The differential expression of ten selected extracellular space genes was further validated using quantitative RT-PCR. Ingenuity Pathway Analysis revealed that some of the affected genes may be associated with cardiovascular system development and function, dermatological diseases and conditions, and cardiovascular disease. POSTN, one of the most downregulated gene candidates in affected individuals, is a matricellular protein with pivotal functions in heart valvulogenesis, skin wound healing, and brain development. Perturbation of PYCR1 expression revealed that it is positively correlated with the POSTN levels. Taken together, POSTN might be one of the key molecules that deserves further investigation for its role in this progeroid neurocutaneous syndrome. [ABSTRACT FROM AUTHOR]

Background: Prader–Willi syndrome (PWS) is a congenital disorder caused by absent expression of paternal genes in 15q11-13 affecting multiple systems. The information concerning the clinical features of this genetic disorder is incomplete in Taiwan. Methods: A retrospective analysis was carried out of 70 PWS patients (39 male, 31 females; age range, 1 month–22 years) seen in four major medical centers in Taiwan from January 1980 through June 2005. All cases were confirmed by methylation-specific polymerase chain reaction. The molecular characteristics, birth history, clinical presentation and laboratory studies were analyzed. Results: Complete genetic analysis was performed in 52 of the 70 patients with PWS. The abnormalities found included deletions in 45 (87%), maternal uniparental disomy (UPD) in five (10%), and a probable imprinting center deletion or an imprinting defect in two (4%). The average weight of the patients at birth was 2588 ± 540 g. Bone age delay of >2 years and growth hormone (GH) deficiency were noted in 11/40 (28%) and 12/20 (60%), respectively. In the 18 in whom both bone age and GH were assessed, abnormalities of both were found in two (11%). In 2000, Taiwan instituted the Rare Diseases and Orphan Drugs Act and mandated a three-phase screening protocol for PWS. Of the 41 patients diagnosed with PWS before 2000, only four (10%) were diagnosed before the age of 3 months; in the 29 patients diagnosed after 2000, in 15 (52%) the syndrome was confirmed before 3 months of age ( P < 0.001). Conclusions: The present finding is in contrast to that of most previous reports that indicated a higher incidence of UPD in PWS. It is unclear whether this discrepancy in the incidence of UPD arises from under-diagnosis or because of ethnic differences, a question worthy of further study. The three-phase screening protocol has generated notable improvement in the early diagnosis of PWS in Taiwan. [ABSTRACT FROM AUTHOR]

Background: This study investigated the survival and natural history of trisomy 13 in a series of patients, comparing the management and outcome before and after the implementation of Taiwan’s National Health Insurance program (NHI). Methods: A total of 28 cases of trisomy 13 seen at Mackay Memorial Hospital, Taipei, Taiwan, from 1985 to 2004 were retrospectively reviewed. Survival and management before (12 cases) and after (16 cases) the implementation of National Health Insurance were compared, and structural defects, imaging findings, and cytogenetic results were analyzed. The cases that were diagnosed prenatally, and finally terminated, were excluded from this study. The diagnosis of trisomy 13 was based on the postnatal chromosome analysis. Results: All patients except one with trisomy 13 translocation died in their first year because of severe malformations of the cardiovascular or central nervous system. The median survival was 9 days. After implementation of National Health Insurance, survival with trisomy 13 was significantly longer than before ( P < 0.05). The three most common structural defects were abnormal auricular helices or low-set ears (89%), cryptorchidism and abnormal scrotum of male (73%) and cleft lip and/or palate (71%). Using echocardiography, the most commonly detected heart defects were patent ductus arteriosus (68%), ventricular septal defect (50%) and atrial septal defect (50%), and eight cases (36%) had complex congenital heart defects. The most common brain lesion was lenticulostriate vasculopathy (22%), followed by holoprosencephaly (17%), brain edema (13%) and subependymal cyst (13%). Conclusions: Early diagnosis and the survival patterns from the data collected should be used to inform parents and health-care professionals to assist in decision making. Although most patients with trisomy 13 die within the first weeks after birth, it is important to recognize that a few may survive the first year. When counseling families, the long-term survival prospects of trisomy 13 patients should be included. [ABSTRACT FROM AUTHOR]