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Population genetic studies of North Asian ethnic groups have focused on genetic variation of sex chromosomes and mitochondria. Studies of the extensive variation available from autosomal variation have appeared infrequently. We focus on relationships among population samples using new North Asia microhaplotype data. We combined genotypes from our laboratory on 58 microhaplotypes, distributed across 18 autosomes, on 3945 individuals from 75 populations with corresponding data extracted for 26 populations from the Thousand Genomes consortium and for 22 populations from the GenomeAsia 100 K project. A total of 7107 individuals in 122 total populations are analyzed using STRUCTURE, Principal Component Analysis, and phylogenetic tree analyses. North Asia populations sampled in Mongolia include: Buryats, Mongolians, Altai Kazakhs, and Tsaatans. Available Siberians include samples of Yakut, Khanty, and Komi Zyriane. Analyses of all 122 populations confirm many known relationships and show that most populations from North Asia form a cluster distinct from all other groups. Refinement of analyses on smaller subsets of populations reinforces the distinctiveness of North Asia and shows that the North Asia cluster identifies a region that is ancestral to Native Americans., (© 2022. The Author(s).)

Microhaplotypes have become a new type of forensic marker with a great ability to identify and deconvolute mixtures because massively parallel sequencing (MPS) allows the alleles (haplotypes) of the multi-SNP loci to be determined directly for an individual. As originally defined, a microhaplotype locus is a short segment of DNA with two or more SNPs defining three or more haplotypes. The length is short enough, less than about 300 bp, that the read length of current MPS technology can produce a phase-known sequence of each chromosome of an individual. As part of the discovery phase of our studies, data on 130 microhaplotype loci with estimates of haplotype frequency data on 83 populations have been published. To provide a better picture of global allele frequency variation, we have now tested 13 more populations for 65 of the microhaplotype loci from among those with higher levels of inter-population gene frequency variation, including 8 loci not previously published. These loci provide clear distinctions among 6 biogeographic regions and provide some information distinguishing up to 10 clusters of populations.

Genetic data on North and Central Asian populations are underrepresented in the literature, especially for autosomal markers. In the present study we used 812 single nucleotide polymorphisms (SNPs) distributed across all the human autosomes and extensively studied at Yale to examine the affinities of two recently collected samples of populations: rural and cosmopolitan Mongolians from Ulaanbaatar and nomadic, Turkic-speaking Tsaatan from Mongolia near the Siberian border. We compare these two populations with each other and with a global set of populations and discuss their relationships to New World populations. Specifically, we analyze data on 521 autosomal loci (single SNPs and multi-SNP haplotypes) studied in 57 populations representing all the major geographical regions of the world. We conclude that these North and Central Asian populations are genetically distinct from all other populations in our study and may be close to the ancestral lineage leading to the New World populations.

Background: At least 40% of those starting onto renal dialysis at the present time are aged over 65 years old. With old age comes increased comorbidity and decreased functional status. The long term management of older patients is limited by the need for rehabilitation and by placement concerns. We describe a 5-year experience of a pilot program, created in 1991 on the recommendation of the Metropolitan Toronto District Health Council, to rehabilitate and care for elderly and disabled patients on either hemodialysis or peritoneal dialysis., Methods and Results: This retrospective, observational study reports on a total of 185 patients admitted over a 5-year period to the Riverdale Chronic Dialysis Unit for chronic care or rehabilitation. The mean age of patients admitted was 67 years (quartiles 61 and 75 years). Eighty-five percent of patients had 2 or more severe comorbidities, while 60% had 3 or more active medical issues. The most commonly used dialysis modality was hemodialysis (80%). Of the 185 patients followed 34% were discharged home, 35% died and 13% were still resident at the time of completion of the study. The most common acute medical problems seen in these patients related to their vascular access and necessitated temporary transfer to an acute nephrology center. A total of 4.7 transfers were recorded for each patient-year of follow up., Conclusions: This study describes the adaptation of facilities already present in our area, to allow better management and placement of older dialysis patients. Transfer of patients from a high level acute care facility to a chronic care facility makes economic and practical sense and may allow better long term health care planning as well as more stability for the family or care-givers.

Objective: To investigate the cost and quality of life associated with the first specialized chronic care facility for disabled dialysis patients., Design: A case controlled study in dialysis patients admitted to a specialized chronic dialysis unit (RCDU)., Setting: The study compares the cost of care in a specialized chronic care facility with that of a tertiary hospital., Patients: All dialysis patients with severe chronic disability, resident in Greater Toronto, who were unable to be discharged into the community and who were admitted to the RCDU in the first year of the program., Interventions: Chronic care and rehabilitation services in a specialized dialysis unit., Outcome Measures: Costs are expressed as $Cdn per patient year. Quality of life scores were measured using SIP and SF-36 questionnaires., Results: The data show a saving of $37,022 Cdn over the 618 day study period with care in the RCDU compared with that of a tertiary hospital. Quality of life measures show no difference in scores., Conclusions: We conclude that this preliminary report confirms a cost benefit of a specialized chronic care dialysis unit.

This study describes the Toronto, Ontario experience with autosomal dominant polycystic kidney disease (ADPKD). Patients were divided into three groups: Group 1, 19 families studied with genetic markers; Group 2, 80 pre-dialysis ADPKD patients followed by Toronto nephrologists in whom the incidence of non-renal complications and the mean age of onset of symptomatology is documented; Group 3, 4,449 individuals who entered end-stage renal failure (ESRF) in the Toronto region between the years 1981 and 1992, 320 with ADPKD and 4129 with other diseases. In this third group age of onset of ESRF, frequency, age and cause of death is compared between ADPKD and non-ADPKD. ADPKD caused by a gene different from that linked to chromosome 16 short-arm probes occurred at a frequency of between 8 and 17%. Incidence of hepatic cysts in ADPKD was similar to that of previous series, other organ involvement was underdiagnosed without deliberate screening, and incidence of symptomatic intracranial aneurysm was 1.25%. A 5% excess of patients with ADPKD died of cerebro-vascular accident. Years of survival after ESRF measured by life table analysis was significantly greater for ADPKD patients than for non-ADPKD patients. A high frequency of death due to infection still exists in ADPKD despite the reduction of invasive procedures in diagnosis and treatment, and despite the presumably improved recent methods of managing infection. The average age of onset of ESRF has been delayed by over six years, and average age of death of ADPKD patients at 63.9 years-old by 12.4 years since 1960.

A family segregating for autosomal dominant polycystic kidney disease (ADPKD) is reported. The clinical picture was typical for ADPKD in some family members, although others showed mild involvement. DNA from family members was probed with seven chromosome 16 single-copy DNA sequences that mapped to the telomere of the short arm of the chromosome. The most likely order of six of the probes from the telomere is palpha3'HVR.64 at the designated locus D16S85, CRI-0327 at D16S63, CRI-090 at D16S45, CRI-0129 at D16S56, CRI-0133 at D16S58, and CRI-0136 at D16S60, with the PKD1 locus for ADPKD between D16S85 and D16S63. The seventh probe 24-1 at D16S80 had not been ordered in relation to the other sequences, but PKD1 had been mapped between it and D16S85. The three probes that were informative in our family, palpha3'HVR.64, CRI-090, and CRI-0136 had been linked to the disease locus at recombination frequencies of 4% and approximately 6 and 12%, respectively. Linkage was excluded between the ADPKD locus in our family and palpha3'HVR.64 at a recombination value of up to 6%. Linkage was also excluded between CRI-090 and the disease locus at a recombination value of up to 5%. The data for linkage between CRI-0136 and the ADPKD locus in our family were inconclusive. Multipoint analysis excluded the possibility that the disease in this family lies between the flanking genetic markers that have previously been used to define the genetic interval in which the most common form of polycystic kidney disease, PKD1, lies. We have not made a positive assignment of the ADPKD mutation in this family.(ABSTRACT TRUNCATED AT 250 WORDS)

Many of the actions previously attributed to pituitary-derived growth hormone are mediated by polypeptide growth factors. These include the insulin-like growth factors I and II (IGF-I and IGF-II), which are members of the insulin family of proteins. We report here the chromosomal mapping of the human genes for IGF-I and IGF-II. IGF-II maps to the short arm of chromosome 11, which also contains the gene for insulin and the proto-oncogene c-Ha-ras1 (ref. 9). IGF-I maps to chromosome 12, which is evolutionarily related to chromosome 11 and carries the gene for the proto-oncogene c-Ki-ras2 (refs 10,44). We have also localized the human gene for an unrelated polypeptide hormone, epidermal growth factor, to chromosome 4q, in the same region as another specialized growth factor, T-cell growth factor. We speculate that these map assignments reflect the existence of gene families involved in growth control.

Alpha 2-macroglobulin (alpha 2M), a high-molecular-weight plasma protease inhibitor has been shown, by both immunological and functional methods, to be produced by cultured adult lung fibroblasts. Cultured skin fibroblasts synthesized approximately one tenth as much alpha 2M as lung fibroblasts. This quantitative difference in alpha 2M production was also demonstrated in fibroblasts of isogenic origin. There was no difference in the amount of alpha 2M produced between adult and fetal fibroblasts of the same tissue type (i.e., of lung or of skin origin). alpha 2M was produced in culture during log-phase growth as well as at confluence. Two other plasma protease inhibitors, C1-esterase inhibitor and a substance immunologically crossreacting with human inter-alpha-trypsin inhibitor, were also made by the cultured fibroblasts. Plasma protease inhibitors not detectable in culture supernatants were alpha 1-antitrypsin, alpha 1-antichymotrypsin, and antithrombin III.

Transforming growth factors (TGF) are defined as biologically active polypeptides which reversibly confer the transformed phenotype onto untransformed cultured cells. They have been subdivided into two classes: type alpha and type beta TGFs. TGF-beta acts synergistically with TGF-alpha in inducing phenotypic transformation. TGF-beta can also act as a negative autocrine growth factor. A human 1050-bp EcoRi cDNA fragment was used to map the human locus for TGF-beta by Southern blotting of DNA prepared from 17 human X Chinese hamster somatic cell hybrids. The human-specific restriction fragments segregated with human chromosome 19 in all of 14 informative hybrids. All other human chromosomes were discordant with the TGF-beta bands in at least four hybrids. After in situ hybridization of the tritiated TGF-beta probe to normal human metaphase spreads, 151 silver grains were scored in 54 cells. Of 24 grains over chromosome 19, 16 grains (11%) lay over region 19q13.1----q13.3. Of the 54 cells analyzed, 16 (30%) had label over region 19q13.1----q13.3. Thus, TGFB is assigned to chromosome 19, subbands q13.1----q13.3. The Tgf-beta locus in the mouse was mapped to chromosome 7 by hybridizing a murine cDNA probe to a Chinese hamster X mouse hybrid panel. Human chromosome 19 and proximal mouse chromosome 7 share another four homologous loci.

Hybridization of probe pDP151 (locus D15S2) to genomic human DNAs digested with EcoRI revealed allelic restriction fragments 9 and 11 kilobase-pairs (kb) in length. Hybridization of pDP151 to EcoRI-digested DNAs from 21 Chinese hamster X human hybrid cell clones containing different subsets of human chromosomes demonstrated cosegregation of the 9 and 11 kb EcoRI fragments with human chromosome 15. D15S2 and two other polymorphic loci previously mapped to chromosome 15--D15S1 and D15S6--were localized to specific regions on human chromosome 15. Eight Chinese hamster X human somatic cell hybrid clones derived from a human donor heterozygous for a balanced translocation between chromosomes 15 and 22 [t(15;22)(q14;q13.3); Oliver et al, Cytogenet Cell Genet 22:503-510, 1978] were studied. After digestion of human and hybrid DNAs with HindIII and Southern blotting, pDP151 (D15S2) and pMS1-14 (D15S1) hybridized to fragments of 4 and 4.5 kb, respectively. Further, pMS1-14 (D15S1) and p9-1a (D15S6) hybridized to EcoRI fragments of 3.5 and 3.2 kb. All fragments cosegregated with the der(22) derivative chromosome containing region 15q14----15qter. In situ hybridization of these probes to normal human chromosomes mapped the corresponding loci with greater precision: D15S1 to 15q15----15q21, D15S2 to 15q15----15q22, and D15S6 to 15q22----15q24.

Serum alpha 2-macroglobulin concentrations were measured in 178 patients with emphysema and 115 control subjects of similar age and sex distribution. The study group included 59 PI type Z patients with alpha 1-antitrypsin deficiency, five with the rare alpha 1-antitrypsin null genotype (PI Q0 or --), and seven with alpha 1-antitrypsin deficiency of the rare PI types MmaltonZ or MduarteZ. Individuals with all types of alpha 1-antitrypsin deficiency were found to have significantly increased serum concentrations of alpha 2M (p less than 0.001). These increased concentrations were associated with all types of alpha 1-antitrypsin deficiency, not only with the PI type Z. The highest alpha 2-macroglobulin concentrations were found in the PI Q0 patients (5 with emphysema, 2 with no lung disease), and these patients had almost no circulating alpha 1-antitrypsin. Raised concentrations of serum alpha 2-macroglobulin were not due to emphysema: 86 patients with emphysema, of PI type M, and the normal control subjects had similar average concentrations of alpha 2-macroglobulin. One control subject with an average alpha 2-macroglobulin concentration of only 41% of normal was found.

Characterization of the 5'-flanking region of the DBP genomic sequence is reported. Nucleotide sequences that serve as cis-regulatory elements for transcription in other genes have been found and include metal regulatory elements, viral enhancers, adipocyte and mitotic signals. The promoter region of DBP is not homologous to the 5'-flanking region of the albumin and alpha-fetoprotein genes despite the strong protein homology and evolutionary relationship among the three proteins.

Transforming growth factors (TGFs) are defined as biologically active polypeptides which reversibly confer the transformed phenotype onto untransformed cultured cells. TGF-alpha shows sequence homology with epidermal growth factor and competes with epidermal growth factor for binding to the epidermal growth factor receptor, stimulating the phosphorylation of the receptor. TGF-alpha is secreted by many transformed cells and may be involved in embryonic development. A cloned human TGF-alpha gene was used to map the locus for the TGF-alpha precursor to the short arm of human chromosome 2, region 2p11----2p13, by Southern blotting techniques with DNA prepared from rodent X human somatic cell hybrids. These hybrids contained different subsets of human chromosomes and included a set with a translocation between human chromosomes 1 and 2 [t(1;2) (q32;q13)]. In situ hybridization of the TGF-alpha probe to normal human metaphase spreads confirmed these data and localized TGF-alpha more precisely to bands 2p11----2p13. Breakpoints in the variant Burkitt lymphoma translocation t(2;8) occur within these bands. Such a t(2;8) translocation could place TGF-alpha next to c-myc in band 8q24. The possibility is raised that TGF-alpha might contribute to tumor progression in these cases of Burkitt's lymphoma.

This paper reports a large kinship with a familial (21;22) translocation occurring in both the balanced and the unbalanced states. Recurrence risks for the (21;22) translocation in the unbalanced state are high (14%) for the offspring of female carriers as compared with those for the offspring of male carriers (4%), but the offspring of male carriers appear to have a much higher risk (50%) of being balanced carriers than those of female carriers (30%).

The genes for the M1 subunit of the enzyme ribonucleotide reductase have been mapped in the human and the murine species by use of two independently derived mouse cDNA clones. Southern blot analysis of rodent x human somatic cell hybrid DNAs confirmed the assignment of RRM1 to the short arm of human chromosome 11. In situ hybridization to human metaphase chromosomes revealed a peak of silver grains over the distal third of band 11p15, a region corresponding to subbands p15.4----p15.5. The mouse Rrml locus was assigned to chromosome 7, where it forms part of a conserved syntenic group of at least seven other genes assigned to human chromosome band 11p15.