Reduction of two functional gamma-globin genes to one: an evolutionary trend in New World monkeys (infraorder Platyrrhini)

Nucleotide sequences were determined for the gamma1- and gamma2-globin loci from representatives of the seven anciently separated clades in the three extant platyrrhine families (Atelidae, Pitheciidae, and Cebidae). These sequences revealed an evolutionary trend in New World monkeys either to inactivate the gamma1 gene or to fuse it with the gamma2 gene, i.e. to have only one functional fetally expressed gamma gene. This trend is clearly evident in six of the seven clades: (i) it occurred in atelids by deletion of most of the gamma1 gene in the basal ancestor of this clade; (ii-iv) in pitheciid titi, saki, and cebid capuchin monkeys by potentially debilitating nucleotide substitutions in the proximal CCAAT box of the gamma1 promoters and (v and vi) in cebid owl and squirrel monkeys by crossovers that fused 5' sequence from gamma1 with 3' sequence from gamma2. In the five clades with gamma1 and gamma2 loci separated by intergenic sequences (the fifth clade being the cebid marmosets), the gamma2 genes retained an unaltered proximal CCAAT motif and their gamma2 promoters accumulated fewer nucleotide substitutions than did the gamma1 promoters. Thus, phylogenetic considerations indicate that the stem platyrrhines, ancestral to all New World monkeys, had gamma2 as the primary fetally expressed gamma gene. A further inference is that when the earlier stem anthropoid gamma gene duplicated, gamma2 (at its greater downstream distance from epsilon) could evade embryonic activation by the locus control region but could be fetally activated once released by regulatory mutations from fetal repressors.

Fetal globin expression in New World monkeys

Reverse phase chromatography of the globin chains of adult, newborn, and fetal erythrocytes from three species of New World monkeys (Cebus apella, Aotus azarae, and Callithrix jacchus) representing three of the seven platyrrhine clades showed that gamma-globin expression was fetal in these animals. The globins were identified by a combination of chemical sequencing and mass spectrometric analysis. Since gamma-globin expression is fetal in the other major simian branch, the catarrhines, but embryonic in prosimian primates and nonprimate placental mammals, the evolution of fetal recruitment can now be assigned to the period between the simian-prosimian divergence (55 million years ago) and the platyrrhine-catarrhine divergence (35 million years ago). The gamma-globin gene underwent tandem duplication during the same evolutionary epoch, in accord with a model that suggests that the downstream duplicated gamma-gene (gamma2) was free to acquire the mutations necessary for fetal recruitment. Mass spectrometric analysis of tryptic digests of the gamma-globins verified the amino acid sequences deduced from genomic sequencing. Detailed analysis of high performance liquid chromatography and matrix-assisted laser desorption/ionization mass spectrometry data showed that gamma2-globin in Cebus was expressed to a far greater extent than gamma1-globin, supporting inferences drawn from a study of the promoter sequences. A "pre-gamma"-globin was observed in C. apella and shown to be primarily the glutathionyl adduct. The other species, A. azarae and C. jacchus, also express only one gamma-globin polypeptide. This work provides biochemical evidence of an evolutionary trend in the platyrrhines to alter the duplicated gamma-globin gene locus so that only one gamma-globin polypeptide is expressed.

Molecular phylogeny of the New World monkeys (Platyrrhini, primates) based on two unlinked nuclear genes: IRBP intron 1 and epsilon-globin sequences

Nuclear sequences of the 1.8 kilobase (kb) long intron 1 of the interstitial retinol-binding protein gene (IRBP), previously determined for 11 of the 16 extant genera of New World monkeys (superfamily Ceboidea, infraorder Platyrrhini), have now been determined for the remaining 5 genera. The maximum parsimony trees found, first with IRBP sequences alone and then with tandemly combined IRBP and epsilon-globin gene sequences from the same species, supported a provisional cladistic classification with the following clusters. Subtribes Callitrichina (Callithrix, Cebuella), Callimiconina (Callimico), Leontopithecina (Leontopithecus) and Saguina (Saguinus) constitute subfamily Callitrichinae, and subfamilies Callitrichinae, Aotinae (Aotus), and Cebinae (Cebus, Saimiri) constitute family Cebidae. Subtribes Chiropotina (Chiropotes, Cacajao) and Pitheciina (Pithecia) constitute tribe Pitheciini; and tribes Pitheciini and Callicebini (Callicebus) constitute subfamily Pitheciinae. Subtribes Brachytelina (Brachyteles, Lagothrix) and Atelina (Ateles) constitute tribe Atelini, and tribes Atelini and Alouattini (Alouatta) constitute subfamily Atelinae. The parsimony results were equivocal as to whether Pitheciinae should be grouped with Atelinae in family Atelidae or have its own family Pitheciidae. The cladistic groupings of extant ceboids were also examined by different stochastic evolutionary models that employed the same stochastic process of nucleotide substitutions but alternative putative phylogenetic trees on which the nucleotide substitutions occurred. Each model, i.e., each different tree, predicted a different multinomial distribution of nucleotide character patterns for the contemporary sequences. The predicted distributions that were closest to the actual observed distributions identified the best fitting trees. The cladistic relationships depicted in these best fitting trees agreed in almost all cases with those depicted in the maximum parsimony trees.

Laparoscopic varicocelectomy for infertility. An initial report from Saudi Arabia

OBJECTIVE

To evaluate laparoscopic varicocelectomy for the treatment of infertility in Saudi males.

METHODS

Between January 1992 and July 1994, laparoscopic varicocele repair was performed at Saudi Aramco Dhahran Health Center, in 48 patients, 8 for pain and 40 for infertility.

RESULTS

The 8 patients with pain improved postoperatively. As for those with infertility, 63% had an improved sperm count and 66% showed increased sperm motility. Thirty percent had no change in motility or count.

CONCLUSION

Laparoscopic varicocelectomy is a simple and safe technique with good results and can be performed as day surgery with early return to normal activity.

DNA evidence on the phylogenetic systematics of New World monkeys: support for the sister-grouping of Cebus and Saimiri from two unlinked nuclear genes

Previous inferences from epsilon-globin gene sequences on cladistic relationships among the 16 extant genera of Ceboidea (the New World monkeys) were tested by strength of grouping and bootstrap values for the clades in the most parsimonious trees found: for this epsilon data set enlarged with additional Cebus and Saimiri orthologues; for another nuclear DNA sequence data set consisting of IRBP (interstitial retinol-binding protein gene) intron 1 orthologues; and for tandemly combined epsilon and IRBP sequences. Different ceboid species of the same genus always grouped strongly together as demonstrated by results on Cebus (capuchin monkeys), Saimiri (squirrel monkeys), Callicebus (titi monkeys), Aotus (night monkeys), Ateles (spider monkeys), and Alouatta (howler monkeys). Other strong groupings that could be represented as monophyletic taxa in a cladistic classification were: Cebuella (pygmy marmoset) and Callithrix (marmoset) into subtribe Callitrichina; Callitrichina, Callimico (Goeldi's monkey), Leontopithecus (lion tamarin), and Saguinus (tamarin) into subfamily Callitrichinae; Callitrichinae, Aotus, Cebus, and Saimiri into family Cebidae; Cacajao (uakari monkey) and Chiropotes (saki) into subtribe Chiropotina; Chiropotina and Pithecia (bearded saki) into tribe Pitheciini; Pitheciini and Callicebus into subfamily Pitheciinae; Brachyteles (woolly spider monkey), Lagothrix (woolly monkey), and Ateles into tribe Atelini; and Atelini and Alouatta into subfamily Atelinae. In addition the epsilon and IRBP results congruently grouped (but at lesser strengths) Brachyteles and Lagothrix into subtribe Brachytelina within Atelini, and also Cebus and Saimiri into subfamily Cebinae within Cebidae. Because the IRBP results weakly grouped Pitheciinae with Cebidae, whereas the epsilon results weakly grouped Pitheciinae with Atelinae, the present evidence is best represented in an interim cladistic classification of ceboids by dividing the superfamily Ceboidea into three families: Atelidae, Pitheciidae, and Cebidae.

Fate of a redundant gamma-globin gene in the atelid clade of New World monkeys: implications concerning fetal globin gene expression

Conclusive evidence was provided that gamma 1, the upstream of the two linked simian gamma-globin loci (5'-gamma 1-gamma 2-3'), is a pseudogene in a major group of New World monkeys. Sequence analysis of PCR-amplified genomic fragments of predicted sizes revealed that all extant genera of the platyrrhine family Atelidae [Lagothrix (woolly monkeys), Brachyteles (woolly spider monkeys), Ateles (spider monkeys), and Alouatta (howler monkeys)] share a large deletion that removed most of exon 2, all of intron 2 and exon 3, and much of the 3' flanking sequence of gamma 1. The fact that two functional gamma-globin genes were not present in early ancestors of the Atelidae (and that gamma 1 was the dispensible gene) suggests that for much or even all of their evolution, platyrrhines have had gamma 2 as the primary fetally expressed gamma-globin gene, in contrast to catarrhines (e.g., humans and chimpanzees) that have gamma 1 as the primary fetally expressed gamma-globin gene. Results from promoter sequences further suggest that all three platyrrhine families (Atelidae, Cebidae, and Pitheciidae) have gamma 2 rather than gamma 1 as their primary fetally expressed gamma-globin gene. The implications of this suggestion were explored in terms of how gene redundancy, regulatory mutations, and distance of each gamma-globin gene from the locus control region were possibly involved in the acquisition and maintenance of fetal, rather than embryonic, expression.

Evidence on primate phylogeny from epsilon-globin gene sequences and flanking regions

Phylogenetic relationships among various primate groups were examined based on sequences of epsilon-globin genes. epsilon-globin genes were sequenced from five species of strepsirhine primates. These sequences were aligned and compared with other known primate epsilon-globin sequences, including data from two additional strepsirhine species, one species of tarsier, 19 species of New World monkeys (representing all extant genera), and five species of catarrhines. In addition, a 2-kb segment upstream of the epsilon-globin gene was sequenced in two of the five strepsirhines examined. This upstream sequence was aligned with five other species of primates for which data are available in this segment. Domestic rabbit and goat were used as outgroups. This analysis supports the monophyly of order Primates but does not support the traditional prosimian grouping of tarsiers, lorisoids, and lemuroids; rather it supports the sister grouping of tarsiers and anthropoids into Haplorhini and the sister grouping of lorisoids and lemuroids into Strepsirhini. The mouse lemur (Microcebus murinus) and dwarf lemur (Cheirogaleus medius) appear to be most closely related to each other, forming a clade with the lemuroids, and are probably not closely related to the lorisoids, as suggested by some morphological studies. Analysis of the epsilon-globin data supports the hypothesis that the aye-aye (Daubentonia madagascariensis) shares a sister-group relationship with other Malagasy strepsirhines (all being classified as lemuroids). Relationships among ceboids agree with findings from a previous epsilon-globin study in which fewer outgroup taxa were employed. Rates of molecular evolution were higher in lorisoids than in lemuroids.

Carba analogues of triglycerides--isosteric mimics for natural lipids. Novel substrates for the determination of regio- and enantioselectivities displayed by lipases

The novel carba analogues 1a,b and 2 were synthesized and demonstrated to be isosteric identical mimics for natural triglycerides. They can be used for the system independent determination of regio- and enantioselectivities displayed by lipases. They are, moreover, attractive starting materials for novel carba analogues of phospholipids, PAF analogues and PAF antagonists.

Molecular phylogeny of the New World monkeys (Platyrrhini, primates)

Phylogenetic relationships among the 16 extant genera of Ceboidea (the New World monkeys) were examined using aligned epsilon-globin gene sequences from 19 New World monkeys (representing all 16 extant ceboid genera), and seven catarrhines (one Old World monkey and six hominoids) and tarsier as the outgroups. The consensus maximum parsimony tree found for these epsilon-globin sequences and the levels of support from parsimony and bootstrap analyses, for the clades in this tree, provided strong evidence for a cladistic classification with the following clusters. Subtribes Callitrichina (Callithrix, Cebuella), Callimiconina (Callimico), Leontopithecina (Leontopithecus), and Saguina (Saguinus) constitute subfamily Callitrichinae, and subfamilies Callitrichinae, Aotinae (Aotus), Saimiriinae (Saimiri), and Cebinae (Cebus) constitute family Cebidae. In turn, subtribes Chiropotina (Chiropotes, Cacajao) and Pitheciina (Pithecia) constitute tribe Pithecini, tribes Pitheciini and Callicebini (Callicebus) constitute subfamily Pitheciinae, tribes Atelini (Brachyteles, Lagothrix, Ateles) and Alouattini (Alouatta) constitute subfamily Atelinae, and subfamilies Pitheciinae and Atelinae constitute family Atelidae. The two families (Cebidae and Atelidae) constitute the Ceboidea, the only extant superfamily of infraorder Platyrrhini. The sister-group relationships of Brachyteles and Lagothrix, Saguinus and Leontopithecus, and Callimico with a Cebuella/Callithrix clade is not as well supported by the parsimony and bootstrap analyses. Therefore, these relationships are not incorporated in the proposed cladistic classification. On determining branch lengths for the ceboid phylogenetic tree from only the more freely evolving noncoding sequences at the epsilon-globin locus and taking the reference age of 35 million years ago (MYA) for the New World monkey-catarrhine branch point, we estimated the age of the atelid-cebid branch point as about 20 MYA, and the ages of the next branch points, those between the subfamilies in each family, as 19-16 MYA.

Divergence between biochemical and cytogenetic differences in three species of the Callicebus moloch group

Specimens from three species of the Callicebus moloch group--C. moloch (N = 80), C. brunneus (N = 166), and C. cupreus (N = 23)--were studied. Twenty genetic loci were investigated through electrophoresis, genetic distances were estimated, and the results compared with the available cytogenetic data. Low values of genetic distance were encountered, contrasting with relatively large chromosome differences. We propose that recent karyotypic rearrangements, rather than other Pleistocene events, were the major evolutionary mechanisms determining speciation in these three taxa.

Chromatographic resolution of chiral intermediates in beta-adrenergic blocker synthesis on chiral stationary phases

The enantiomeric purities of optically active intermediates for beta-adrenergic blocking agents prepared via enzyme-assisted processes can be determined rapidly and with high accuracy using HPLC on commercially available columns with chiral supports [Chiralcel OD, OB; Chiralpak OT(+)]. The dependence of the resolution parameters on the substitution pattern of both hydroxy compounds and their esters is reported.

Genetic studies in three South American black populations

Twenty-one genetic systems were investigated in three relatively isolated South American Black populations. Unexpected allele frequencies were found in different systems in all populations, suggesting the occurrence of genetic drift and/or founder effects. The estimates of racial admixture indicate 50% to 79% of Black ancestry, with various degrees of White (18%-28%) and Amerindian (3%-32%) ancestry.

Coat color and biochemical variation in Amazonian wild populations of Alouatta belzebul

A comparative study of 13 blood genetic systems and pelage color variation was performed in four wild populations of Alouatta belzebul. The animals from the west bank of the Tocantins River showed less color variation than those from the east bank, as well as less than those from Tocantins Island. The blood genetic markers, however, revealed an opposite pattern of variation. A previously undescribed morphological variant (completely red) was observed in one specimen of the east bank, where pelage color of the local population varied from completely black to completely red. Levels of heterozygosity and inter- and intralocus variances for the blood systems are compared with those observed in five other species of New World primates.

Transferrin and albumin polymorphisms in buffaloes from Brazil

Starch gel electrophoresis disclosed six transferrin phenotypes, explainable by three alleles (TF A, TF D, TF E), and three albumin phenotypes, determined by two alleles (ALB A, ALB B). Their prevalences suggest that the Brazilian populations have admixed river and swamp buffalo ancestry, the frequency of ALB A being much higher than those found in other regions.

Mesenteric venous thrombosis due to antithrombin III deficiency

A 19-year-old woman developed gradually worsening abdominal pain, signs of peritonitis, and hematemesis. Laparotomy revealed peritonitis due to segmental small-bowel infarction, and the underlying pathologic condition was mesenteric vein thrombosis. A primary thrombotic disorder was suggested and antithrombin III deficiency was found. Before anticoagulant therapy could be initiated, she developed hemorrhagic cerebral infarction and died. Her history included three episodes of deep vein thrombosis while taking oral contraceptives. Her father died of spontaneous mesenteric and portal vein thrombosis at age 29 years. This report underlines the importance of careful interpretation of the vascular pathology in cases of intestinal ischemia.