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Norrie disease (ND) is an X‐linked disorder, inherited as a recessive trait that, therefore, mostly affects males. The gene responsible for ND, called NDP, maps to the short arm of chromosome X (Xp11.4‐p11.3). We report here an atypical case of ND, consisting of a patient harboring a large submicroscopic deletion affecting not only the NDP gene but also the MAOA, MAOB, and EFHC2 genes. Microarray comparative genomic hybridization (CGH) analysis showed that 11 consecutive bacterial artificial chromosome (BAC) clones, mapping around the NDP gene, were deleted. These clones span a region of about 1 Mb on Xp11.3. The deletion was ascertained by fluorescent in situ hybridization (FISH) analysis with different BAC clones located within the region. Clinical features of the proband include bilateral retinal detachment, microcephaly, severe psychomotor retardation without verbal language skills acquired, and epilepsy. The identification and molecular characterization of this case reinforces the idea of a new contiguous gene syndrome that would explain the complex phenotype shared by atypical ND patients. © 2007 Wiley‐Liss, Inc.

Fragile X syndrome (FXS) is the commonest cause of inherited mental retardation in males. Even though this affirmation is repeated in virtually all papers referring to FXS, the precise frequency of this syndrome in the general population is unknown. We present a general population screening analyzing an anonymous series of 5,000 consecutive newborn males from the neonatal screening program of the population of Catalonia in Spain. The aim of the study is to determine the incidence of FXS via a simple and economical methodology based on the nonamplification of the fragment containing the CGG repeats of the FRAXA locus in the samples carrying alleles over 52 repeats. From the initial 5,000 samples, 4,920 were in the normal range, 15 gave rise to bands with more than 52 repeats (11 corresponded to intermediate alleles and four premutated alleles). After further studies, two samples were considered to be carriers of full mutations. According to these results, the incidence of FXS affected newborn males is 1 in 2,466, and 1 in 1,233 males is a carrier of the premutation. We can deduce that 1 in 8,333 is an affected female with clinical manifestations and 1 in 411 will be a premutation carrier woman. Upon reviewing the literature, there seems to be variability in the frequencies found by the different groups. Therefore, given that our study is limited to the Catalan population in Spain, these results should be taken as valid for the Catalan region and should only be extrapolated to other populations with caution.

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To study the sonographic pattern of autosomal recessive polycystic kidney disease (ARPKD) in early adulthood in order to identify imaging criteria to diagnose this disease and to distinguish between recessive and autosomal dominant polycystic kidney disease (ADPKD) in that age group.

Fragile X syndrome, the most common form of familial mental retardation, is mainly caused by the expansion of an unstable region of CGG repeats in the 5′ untranslated region of the FMR1(Fragile X Mental Retardation-1) gene. Molecular tools to detect an abnormal CGG expansion in FMR1include Southern blot hybridization and PCR amplification. Southern blotting with the StB12.3 probe and EcoRI/EagI double digestion is widely used as a routine test for fragile X syndrome diagnosis in laboratories around the world. A patient with mental retardation of unknown origin showed absence of digestion for EagI due to a −149C→G substitution in the CpG island of theFMR1gene, which destroys that restriction enzyme site. Screening for other changes around that region also detected a −154insGGC in a patient with a phenotype highly suggestive of fragile X syndrome but without CGG expansion. Expression studies did not show any abnormal changes in FMR1function. In summary, we have identified two different changes (a C to G substitution at −149 and a GGC insertion at −154) in the promoter of the FMR1gene. These are the first variants described in the promoter of the FMR1gene.

The fragile X syndrome is due to an expansion of the CGG trinucleotide repeat in the FMR1 gene and hypermethylation of its 5' upstream CpG island in about 95% of the cases. The remaining 5% of cases correspond to other molecular alterations in FMR1 gene such as partial or complete deletions, or point mutations within the coding sequence. We selected 31 patients with clinical manifestations of fragile X syndrome, scoring 16 or more in Hagerman's checklist, but without the CGG expansion. We performed single-strand conformation polymorphism analysis using a nonradioactive technique (silver staining) and we detected six anomalous migrations that, by sequence analysis, corresponded to six nucleotide changes. We screened two different populations (control and fragile X) for these changes, and concluded that they correspond to five new polymorphisms within the FMR1 gene and to one possible synonymous mutation. Am. J. Med. Genet. 84:262–265, 1999. © 1999 Wiley-Liss, Inc.

Genetic heterogeneity is a well-known feature of Alport syndrome (AS). Most families with AS show an X-linked dominant pattern of inheritance but about 15% of families show an autosomal inheritance of the disease. Autosomal recessive AS may account for 10% of the total number of cases and is caused by mutations in the COL4A3 and COL4A4 genes. The clinical spectrum of this rare disorder has not been well clarified.

Tuberous sclerosis (TSC) and autosomal dominant polycystic kidney disease (ADPKD) are genetically heterogeneous diseases. The major gene for ADPKD (PKD1) lies adjacent to the TSC2 gene on chromosome 16p13. Some reports in the literature referred to an unusual presentation of TSC with enlarged cystic kidneys at birth, but it was not until the localization of the TSC2 and PKD1 genes that it was possible to analyze the interaction between both genes. We describe a case of a child with TSC and enlarged cystic kidneys. The study of genetic marker segregation in the family pointed to the presence of a deletion involving the 3' region of PKD1. A further study of the region showed a deletion of 40 kb involving both PKD1 and TSC2. We suggest that an additive or synergistic effect between PKD1 and TSC2 may cause this renal phenotype. A contiguous gene syndrome involving PKD1 and TSC2 should be suspected in children with TSC and enlarged polycystic kidneys at birth. The first approach to identify a deletion of both genes could be the analysis of the segregation of PKD1 and TSC2 markers in the family. (Am J Kidney Dis 1998 Jun;31(6):1038-43)

In this Letter the results of applicability of Kirchhoff 's law as given by Salisbury and coworkers are discussed. In their paper, experimental evidence on the violation of Kirchhoff 's law for heterogeneous temperature regimes was given. In this Letter the hypothesis of the existence of a single 'sample temperature' resulting in measured emissivities which were less than the true values was demonstrated. Thus, the 'evidence' given by Salisbury and coworkers needs reviewing.

In this Letter we present a simple technique for estimating surface temperatures from data obtained by means of a thermal infrared radiometer. The technique is based simply on the use of a table and a graph, from which cmissivity and atmospheric effects are easily evaluated. The accuracy is better than a tenth of a degree when emissivity and atmospheric radiance arc known.

In this paper we have developed some improvements in order to obtain accurate Sea Surface Temperature (SST) maps with APT (Automatic Picture Transmission) data transmitted in real time from NOAA satellites. The methodology proposed can be profitable for any user interested in accurate retrievals of SST such as meteorologists, climatologists and oceanographers. APT data are converted to 10-bit digital data like in HRPT images in order to perform calibration. Geometric correction is achieved with a subpixel accuracy for APT images. Small clouds are avoided by means of the technique of universal kriging. A single-channel method using radiosounding data has been developed for the atmospheric and emissivity corrections. Atmosphere has been radiometrically characterized for the whole image (3000km wide), and atmospheric correction can always be achieved with an error better than 0.5 deg K when accurate data of coincident atmospheric profiles is used. At the worst, when there are no such radiosoundings, SST can be determined with a standard error of estimate of 1.1 deg K (compared with split-window technique) or 1.3 deg K (compared with in situ data).

In this paper we have developed some improvements on the commonly used methodologies in order to obtain accurate maps of sea surface temperature (SST). These improvements permit us: (1) to calibrate without bias AVHRR channels including non-linear corrections; (2) to get geometrically corrected maps for the complete scan width of AVHRR (3000 km) with a subpixel accuracy; (3) to detect clouds over the sea; and (4) to make atmospheric and emissivity correction for all zenith angles from nadir to the outermost off-nadir view of AVHRR images (68.9 ) and for different types of atmospheres. The theoretical base of the improvements used is detailed in each section, and an example is also included in each section in order to better explain how they are applied in a practical situation. The methodologies developed here can be profitable for any user interested in accurate retrievals of SST such as meteorologists, climatologists and oceanographers.

Huntington's disease is an autosomal dominant neurodegenerative disorder caused by the expansion of a (CAG)_n repeat in the IT15 gene. Three per cent of cases are sporadic and in those in which family studies have been performed, the origin of the mutation was always paternal. The first sporadic case of Huntington's disease is presented in which a premutated maternal allele of 37 CAG repeats was transmitted expanded to the proband (43 CAG repeats). Molecular analysis of the IT15 gene is extremely important in sporadic cases of Huntington's disease, providing correct diagnosis of the disorder and facilitating genetic counselling to the family members.