A sterile male with 45,X0 and a Y;22 translocation

Summary Cytogenetic analysis of a 20-year-old sterile male revealed a 45,X0 karyotype with no evidence for Y-chromosomal material on any of the chromosomes analysed by Q-, G- and C-banding. DNA analysis with 17 different Y chromosome-derived probes revealed the presence of Yp DNA sequences in the patient's genome. In situ hybridization with the Yp-derived probe pJA36B disclosed a translocation of Y-chromosomal material onto the short arm of a chromosome 22.     

Localization of the active gene of aldolase on chromosome 16, and two aldolase A pseudogenes on chromosomes 3 and 10

Summary Southern blot analysis of human genomic DNA hybridized with a coding region aldolase A cDNA probe (600 bases) revealed four restriction fragments with EcoRI restriction enzyme: 7.8 kb, 13 kb, 17 kb and >30 kb. By human-hamster hybrid analysis (Southern technique) the principal fragments, 7.8 kb, 13 kb, >30 kb, were localized to chromosomes 10, 16 and 3 respectively. The 17-kb fragment was very weak in intensity; it co-segregated with the >30-kb fragment and is probably localized on chromosome 3 with the >30-kb fragment. Analysis of a second aldolase A labelled probe protected against S1 nuclease digestion by RNAs from different hybrid cells, indicated the presence of aldolase A mRNAs in hybrid cells containing only chromosome 16. Under the stringency conditions used, the EcoRI sequences detected by the coding region aldolase A cDNA probe did not correspond to aldolase B or C. The 7.8-kb and >30-kb EcoRI sequences, localized respectively on chromosomes 10 and 3, correspond to aldolase A pseudogenes, the 13-kb EcoRI sequence localized on chromosome 16 corresponds to the aldolase active gene. The fact that the aldolase A gene and pseudogenes are located on three different chromosomes supports the hypothesis that the pseudogenes originated from aldolase A mRNAs, copied into DNA and integrated in unrelated chromosomal loci.     

A novel autonomously replicating sequence (ARS) for multiple integration in the yeast Hansenula polymorpha DL-1.

Several autonomously replicating sequences of Hansenula polymorpha DL-1 (HARSs) with the characteristics of tandem integration were cloned by an enrichment procedure and analyzed for their functional elements to elucidate the mechanism of multiple integration in tandem repeats. All plasmids harboring newly cloned HARSs showed a high frequency of transformation and were maintained episomally before stabilization. After stabilization, the transforming DNA was stably integrated into the chromosome. HARS36 was selected for its high efficiency of transformation and tendency for integration. Several tandemly repeated copies of the transforming plasmid containing HARS36 (pCE36) integrated into the vicinity of the chromosomal end. Bal 31 digestion of the total DNA from the integrants followed by Southern blotting generated progressive shortening of the hybridization signal, indicating the telomeric localization of the transforming plasmids on the chromosome. The minimum region of HARS36 required for its HARS activity was analyzed by deletion analyses. Three important regions, A, B, and C, for episomal replication and integration were detected. Analysis of the DNA sequences of regions A and B required for the episomal replication revealed that region A contained several AT-rich sequences that showed sequence homology with the ARS core consensus sequence of Saccharomyces cerevisiae. Region B contained two directly repeated sequences which were predicted to form a bent DNA structure. Deletion of the AT-rich core in region A resulted in a complete loss of ARS activity, and deletion of the repeated sequences in region B greatly reduced the stability of the transforming plasmid and resulted in retarded cell growth. Region C was required for the facilitated chromosomal integration of transforming plasmids.     

Human papillomavirus type 6 long control region and human cellular DNA contain related sequences.

We have identified a region of human papillomavirus type 6 (HPV-6) DNA that hybridizes with human cellular DNA containing no detectable HPV DNA sequences. The region of hybridization has been localized to a segment of the viral long control region between the end of the L1 open reading frame and the late polyadenylation signal and is likely contained within a 94-base-pair insertion at nucleotide 7350 which is present in the cloned HPV-6b DNA used for these studies. Restriction fragments of HPV-6 DNA from seven patients suggested that this insert was present in these naturally occurring viral genomes as well. The presence of this insert was confirmed by direct sequence analysis of polymerase chain reaction-amplified segments from four naturally occurring HPV-6 genomes. By analogy with other systems, this insert and surrounding sequences may function to destabilize the HPV-6 late mRNA.     

Isolation and identification of a novel tandemly repeated DNA sequence in the centromeric region of human chromosome 8

EcoRI subclones, designated as 50E1 and 50E4, were independently obtained from a cosmid clone previously mapped to the centromeric region of human chromosome 8. Southern blot hybridization analyses suggested that both subclones contain repetitive DNA sequences different from the chromosome 8 specific alphoid DNA. DNA sequence analysis of the 704 bp insert of 50E1 and the 1, 962 bp insert of 50E4 revealed that both inserts contained tandemly repeated units of 220 bp. Fluorescence in situ hybridization studies confirmed these two subclones to be specifically located on the centromeric region of chromosome 8. A 220 bp consensus sequence, derived from nine monomeric repeats, showed no significant homology to alphoid consensus sequences or to other currently known human centromeric DNA sequence. Furthermore, no significant homology was found with any other DNA sequence deposited in the EMBL or GenBank databases, indicating that this chromosome 8 specific repetitive DNA sequence is novel. From slot blot experiments it was estimated that 0.013% of the human genome comprises 1,750 of these monomeric repeats, residing on the centromeric region of chromosome 8 in tandem array(s).