Congenital muscular dystrophy type 1A (MDC1A) is caused by mutations in the LAMA2 gene encoding laminin‐α2. We describe the molecular study of 26 patients with clinical presentation, magnetic resonance imaging and/or laminin‐α2 expression in muscle, compatible with MDC1A. The combination of full genomic sequencing and complementary DNA analysis led to the particularly high mutation detection rate of 96% (50/52 disease alleles). Besides 22 undocumented polymorphisms, 18 different mutations were identified in the course of this work, 14 of which were novel. In particular, we describe the first fully characterized gross deletion in the LAMA2 gene, encompassing exon 56 (c.7750‐1713_7899‐2153del), detected in 31% of the patients. The only two missense mutations detected were found in heterozygosity with nonsense or truncating mutations in the two patients with the milder clinical presentation and a partial reduction in muscle laminin‐α2. Our results corroborate the previous few genotype/phenotype correlations in MDC1A and illustrate the importance of screening for gross rearrangements in the LAMA2 gene, which may be underestimated in the literature.

Adrenoleukodystrophy (ALD), a lethal demyelinating disease of the brain, is caused by mutations of a gene encoding an ATP-binding transporter, called ALDP, localized in the peroxisomal membrane. It is associated with a defective oxidation of very-long-chain fatty acids, leading to their accumulation in many tissues. This study reports that the retroviral-mediated transfer of the ALD cDNA restored very-long-chain fatty acid oxidation in ALD fibroblasts in vitro following abundant expression and appropriate targeting of the vector-encoded ALDP in peroxisomes. The same method may be used in hematopoietic cells as a further step of a gene therapy approach of ALD.X chromosome-linked adrenoleukodystrophy (ALD) is a devastating neurologic disorder that affects 1/15,000 males with different clinical phenotypes within the same kindred. The cerebral lesions occur in young boys between the age of 5 and 12 years and are characterized by progressive demyelination leading to rapid deterioration and death within 3-5 years of diagnosis (1).The main biochemical defect of ALD is an impaired oxidation of saturated very-long-chain fatty acids (VLCFAs) and their accumulation in cerebral white matter, adrenal glands, fibroblasts, and plasma (1, 2). In ALD fibroblasts, VLCFAs are normally transported across the peroxisomal membrane (3), but a functional defect of VLCFA-CoA synthetase impairs their (3-oxidation (4-6).The recent cloning and demonstration of deletions and mutations of theALD gene (7-10) revealed that the metabolic abnormality is due to defects of a 75-kDa peroxisomal integral membrane protein (11), a member of the ATP-binding cassette (ABC) transporter family (12). The function of ALD protein (ALDP) is unknown, but it is necessary for the activity of the VLCFA-CoA synthetase, also localized in the peroxisomal membrane (13).Various therapeutic approaches including a lipid diet combining the administration of glycerol trioleate and trierucate (Lorenzo's oil) (14-16) failed to modify the evolution of the cerebral lesions of ALD. Four years ago, we reported that bone marrow transplantation (BMT) can reverse demyelination, if performed at a relatively early stage of its development (17). Since allogenic BMT is often limited by the lack of histocompatible donors and has serious secondary effects, we considered transplantation of the patient's own bone marrow cells after transfer of the normal ALD gene as an alternative strategy.The publication costs of this article were defrayed in part by page charge payment. This article must therefore be hereby marked "advertisement" in accordance with 18 U.S.C. §1734 solely to indicate this fact. Fig. 1A), a 2.43-kb Spe I-EcoRI fragment was isolated from the fulllength human ALDP cDNA, Bcl I linkered, and inserted in the sense orientation into the unique BamHI restriction site of the M48 retroviral vector, a Moloney-based retroviral vector (19). In this M48-ALD construct, expression of ALD cDNA is under the control of the mouse phosphoglycerate kinase (PGK) gene promoter.The GLU-3...

Objective: Defects in the human thyroid peroxidase (TPO) gene are reported to be one of the causes of congenital hypothyroidism (CH) due to a total iodide organification defect. The aim of the present study was to determine the nature and frequency of TPO gene mutations in patients with CH, characterised by elevated TSH levels and orthotopic thyroid gland, identified in the Portuguese National Neonatal Screening Programme. Subjects and methods: The sample comprised 55 patients, from 53 unrelated families, with follow-up in the endocrinology clinics of the treatment centres of Porto and Lisbon. Mutation screening in the TPO gene (exons 1-17) was performed by single-strand conformational analysis followed by sequencing of fragments with abnormal migration patterns. Results: Eight different mutations were detected in 13 patients (seven homozygotes and six compound heterozygotes). Novel mutations included three missense mutations, namely 391T . C (S131P), 1274A . G (N425S) and 2512T . A (C838S), as well as the predictable splice mutation 2748G . A (Q916Q/spl?). The undocumented polymorphism 180-47A . C was also detected. Conclusion:The results are in accordance with previous observations confirming the genetic heterogeneity of TPO defects. The proportion of patients in which the aetiology was determined justifies the implementation of this molecular testing in our CH patients with dyshormonogenesis.