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J L Mandel

Publications and source records attributed to J L Mandel.

At least 235 records · Page 13Linked to original sources
PubMed1978

Organization of coding and intervening sequences in the chicken ovalbumin split gene.

The interruptions in the chicken ovalbumin gene which were reported previously (Breathnach, Mandel and Chambon, 1977) are shown to be due to the presence of intervening sequences which separate the messenger-coding sequences. We present evidence for an additional interruption of the gene, which, together with those reported earlier and by Garapin et al. (1978b), make a total of six intervening sequences. All of these intervening sequences are located in the DNA region that corresponds to the part of the ov mRNA which codes for amino acids. The seven coding fragments of the split ovalbumin gene are arranged in the same order and relative orientation as in the ovalbumin double-stranded cDNA. All the sequences coding for ov mRNA are contained in a chromosomal DNA region of 6000 bp, which is more than 3 times longer than ov mRNA. The general organization of the ovalbumin split gene is discussed.

Animals↗
PubMed1977

Ovalbumin gene is split in chicken DNA.

The ovalbumin gene, is split in chicken DNA. Two interruptions in the sequences coding for ovalbumin mRNA have been detected, at least one of them lying in the protein coding sequence. The unexpected gene organisation is present both in oviduct cells highly specialised in ovalbumin synthesis and in erythrocytes.

Animals↗
PubMedDate not supplied

Linkage analysis suggests at least two loci for X-linked non-specific mental retardation.

Epidemiological studies have suggested that non-specific X-linked mental retardation (XLMR) might be at least as frequent as the fragile X syndrome. The identification of all mutations causing XLMR would thus appear of prime importance. In the absence of other clinical signs the problem of genetic heterogeneity is acute. This can be partly overcome by the analysis of large families. We have been able to perform linkage analysis in 3 such families. The condition in family 1 was described as clinically resembling the fra (X) syndrome by Proops et al [1983]: the kindred includes 7 affected males in 3 sibships. Family 2 from Denmark has affected males in 4 generations; however, several affected relatives in this extended pedigree are deceased. Family 3 from France counts 6 affected males in two sibships. The families were analysed with about 25 X-linked markers. Linkage with markers in Xp22.2-p22.3 was found in family 1: z(theta) = 2.62 at theta = 0.06 for DXS85 (probe 782). Suggestion of linkage was found in family 2 with both the Duchenne muscular dystrophy region (DXS164 in Xp21.2) and with DXS1 (Xq11-q12). In family 3, DXS159 (Xq12-q13) gave a lod score of 2.53 at theta = 0; results were compatible with localisation of the putative XLMR locus in this family proximal to DXYS1 (Xq21). These data suggest that at least two non-specific XLMR loci could exist, one in Xp22 and the other in the q12-q13 region.

Chromosome Mapping↗
PubMedDate not supplied

Probable localisation of the Coffin-Lowry locus in Xp22.2-p22.1 by multipoint linkage analysis.

The Coffin-Lowry syndrome (McKusick No. 30360) is a rare genetically transmitted disorder characterized by severe mental retardation, "coarse" facial appearance, thick soft skin, tapering fingers, and progressive skeletal abnormalities. X-linked inheritance is implied since the males are severely affected with variably mild manifestations in carrier women. We have performed a linkage analysis with many X-linked RFLP markers in 4 families. Positive two-point lod scores were obtained with DXS28 (z(theta) = 2.00 at theta = 0.05) and DXS41 (z(theta) = 1.26 at theta = 0.10). We performed a 5-point linkage analysis using the LINKMAP program assuming that DXS16 and DXS43 are a single locus and using the following fixed map (distances in centimorgans): DXS85 - 18cM - (DXS16, DXS43) - 13cM - DXS41 - 5cM -DXS28. This gave a multipoint lod score of 3.41 for a localisation in Xp22.2-p22.1, between DXS43 and DXS41.

Bone Diseases, Developmental↗
PubMedDate not supplied

Improved DNA markers for efficient analysis of fragile X families.

We report the characteristics of two new probes that detect BclI RFLPs useful for analysis of fragile X families. With these two probes and a single blot, 34% of women are heterozygous both for the proximal marker DXS105 (closer to the fragile X locus than the factor IX gene) and for the distal markers DXS52 or the factor VIII gene. Combined with the analysis of previously described polymorphic markers, it is possible to have a majority of families fully informative for flanking markers using a limited number of probes and restriction digests.

DNA Probes↗