No pathogenic mutations in the beta-synuclein gene in Parkinson's disease

We present 11 families consistent with autosomal dominant inheritance of probable Parkinson's disease (PD). Although excluded as a cause of disease in these kindreds, mutations in the alpha-synuclein gene have been implicated in familial PD. The beta-synuclein gene is highly homologous, expressed in the nervous system and thus is a good candidate gene for PD. Multipoint linkage analysis was either equivocal or excluded 5q35 haplotype sharing among affected family members. Sequencing the translated exons of the beta-synuclein gene failed to identify any pathogenic mutation.

Unhealthy effects of atmospheric temperature and pressure on the occurrence of myocardial infarction and coronary deaths. A 10-year survey: the Lille-World Health Organization MONICA project (Monitoring trends and determinants in cardiovascular disease)

BACKGROUND

Associations between an increase in coronary heart disease occurrence and low atmospheric temperatures have been reported from mortality data and hospital admission registries. However, concomitant increases in noncardiovascular case fatality rates and selection bias of hospital cases may weaken this observation. In this study, we addressed the question of the relationships between fatal and nonfatal coronary diseases and meteorological variables in 10-year data (1985 to 1994) collected in a morbidity registry (Lille-WHO MONICA Project) monitoring 257 000 men from 25 to 64 years of age.

METHODS AND RESULTS

The impacts of atmospheric temperature (in Celsius) and pressure (in millibars) on daily rates of myocardial infarction (MI) and coronary deaths were studied. Percentages of variation of event rates according to meteorological variations were derived from the relative risks estimated with a Poisson regression model. During the 10-year longitudinal survey, 3616 events occurred. Rates of events decreased linearly with increasing atmospheric temperature. For atmospheric pressure, we detected a V-shaped relationship, with a minimum of daily event rates at 1016 mbar. A 10 degrees C decrease was associated with a 13% increase in event rates (P<0.0001); a 10-mbar decrease <1016 mbar and a 10-mbar increase >1016 mbar were associated with a 12% increase (P=0.001) and an 11% increase (P=0. 01) in event rates, respectively. These effects were independent and influenced both coronary morbidity and mortality rates, with stronger effects in older age groups and for recurrent events.

CONCLUSIONS

This longitudinal study is the first to estimate the attributable effect of meteorological variables on MI morbidity in population and strongly argues for a systematic fight against cold in cardiovascular disease prevention, particularly in older ages and after a first MI.

Risk of dementia in parents of probands with and without the apolipoprotein E4 allele. The EVA study

STUDY OBJECTIVE

Age, family history of dementia and the epsilon 4 allele of the apolipoprotein E gene have been associated with Alzheimer's disease (AD). Considering the strength of APOE-epsilon 4 as a genetic risk factor for AD, this factor might explain a large part of the association between AD and a family history of dementia. Therefore, in the general population, a higher frequency of dementia should be observed among parents of probands with at least one epsilon 4 allele than in parents of probands without this allele.

DESIGN, SETTING, AND PARTICIPANTS

The study investigated a sample of 1153 volunteers between 59 and 71 years old, genotyped for the APOE gene, all participating in the EVA study. Dementia in their parents was determined using a self reported questionnaire.

MAIN RESULTS

The frequency of dementia in 2164 parents was examined and it was found that 245 were demented. The percentage of demented parents was 13.0% in the subgroup of parents of subjects having one or two epsilon 4 alleles and 10.8% in the other subgroup. The relative risk of dementia among parents according to the APOE-epsilon 4 status of probands, was calculated using a Cox model adjusted for the educational level of parents and their history of stroke: RR = 1.21 (95% CI 0.90, 1.63).

CONCLUSION

This lack of association supports the observation that in the general population, APOE-epsilon 4 cannot explain a large part of family history of dementia.

[Treatment of complicated renal colic in patients treated with indinavir: value of double J stents]

OBJECTIVE

Evaluation of the treatment of complicated ureteric stones in patients treated with indinavir.

PATIENTS AND METHODS

From March 1997 to May 1998, 10 patients (7 males, 3 females, aged 30 to 56 years), treated by triple combination therapy for HIV infection, were drained for stones attributed to indinavir (CRIXIVAN), which had become obstructive and complicated. The duration of treatment with indinavir ranged from 14 days to 2 years. No patient had a history of urological disease. One patient presented with bilateral stones. All patients presented complicated clinical features: fever in 3 cases; severe pain in 8 cases, with delayed excretion more than 4 hours on IVU in 6 cases. All stones were radiolucent except for one slightly radioopaque stone. The stone was situated in the lumbar ureter in 3 cases, iliac ureter in 1 case and pelvic ureter in 8 cases.

RESULTS

In 10 out of 11 cases, a double J stent was inserted, preceded by drainage by simple ureteric catheter (infected urine) in 1 case and by percutaneous nephrostomy (PCN) with antegrade insertion of the stent (failure of the retrograde route) in 1 case. No complementary stone fragmentation or extraction treatment was necessary after this procedure. Stents were left in place for 3 to 7 weeks. In one case, a stone of the lumbar ureter required PCN followed by extracorporeal lithotripsy.

CONCLUSION

In the case of complications requiring a urological procedure, insertion of a double J stent allows curative treatment of very friable indinavir stones, which are fragmented by passage of the stent.

Is the LDL receptor-related protein involved in Alzheimer's disease?

LDL-related protein receptor (LRP) is the main receptor in the brain for apolipoprotein E. Moreover, the LRP gene is located on chromosome 12, the site of a potential Alzheimer's disease (AD) locus. We explored the association between the LRP gene and AD in 600 French Caucasian patients (37.8% men, mean age 72.0+/-8.0 years, mean age at onset 68.7+/-8.1 years) and age-matched controls (n=646, 37.0% men, mean age 72.5+/-8.2 years) and observed an association between a (TTTC) repeat at the 3' end of an Alu sequence in the LRP gene and the risk of developing AD. Three alleles were detected in this population [corresponding to 83, 87, and 91 base pairs (bp)], the 91-bp allele being associated with an increased risk of developing AD [all patients: odds ratio (OR) 1.6, P<0.01; late-onset AD: OR 1.8, P<0.01]. This suggests an association between the LRP locus and AD. However, in the light of studies related to the exon 3 LRP polymorphism and given the low strength of the association reported here, a biologically active variant may exist on chromosome 12, either in the LRP gene itself or in another gene in the vicinity.

[Renal retransplantation in adults. Comparative prognostic study]

For a long time, retransplanted patients were considered to be high-risk subjects, but a number of studies have shown that retransplantation can give good short-term results.

OBJECTIVES

Between October 1987 and February 1997, 51 retransplanted patients (Group 1) were compared with 96 patients (Group 2), matched for age, sex and date of transplantation, receiving a first kidney, with a mean age of 41 +/- 10 years and a mean follow-up of 44 +/- 32 months.

RESULTS

The patient did not differ in terms of aetiology of the renal disease, mismatches and duration of dialysis before the first transplant and the duration of dialysis before the second transplant was 53 +/- 54 months. In Group 1, transplant loss was due to an immunological [34], surgical [8], or medical [3] cause, or due to recurrence of the disease [3] and discontinuation of treatment [5]. Hyperimmunized subjects were more numerous in Group 1: 21.4% vs 5.2% (p < 0.01). Immunosuppression only differed in terms of Cyclosporin: 65% for Group 1 vs 45% for Group 2 (p < 0.05). The two groups did not differ in terms of acute rejection (33% for Group 1 vs 48% for Group 2), serum creatinine at last review (140 +/- 51 +/- 65 m mol/l) and 5-year and 8-year patient (92 vs 82% and 92 vs 76%) and graft survival curves (85 vs 75% and 59 vs 61%).

CONCLUSION

This study confirms that retransplantation can be successfully performed, even in terms of long-term results.

Conversion of patients with rheumatoid arthritis from the conventional to a microemulsion formulation of cyclosporine: a double blind comparison to screen for differences in safety, efficacy, and pharmacokinetics

OBJECTIVE

To assess whether patients with rheumatoid arthritis (RA) may be converted, on a milligram-to-milligram basis, from conventional cyclosporin A (CyA, Sandimmun) to the microemulsion formulation (Neoral) with maintenance of longterm safety, and to compare cyclosporin A (CyA) pharmacokinetics between formulations.

METHODS

In this double blind, multicenter, parallel group study, 51 patients receiving stable conventional CyA maintenance treatment were randomized to continue conventional CyA (n = 27) or to convert to CyA microemulsion (n = 24) and were monitored for 52 weeks. Trough blood CyA levels were measured before and at intervals after conversion. CyA steady-state area under the curve was assessed one week before and 2 and 6 weeks after randomization in 15 patients in each treatment arm. CyA trough levels and pharmacokinetic results remained unknown to investigators throughout the study. CyA doses were titrated as necessary on the basis of clinical evaluation and disease activity assessments.

RESULTS

Initial mean daily doses were 3.5 mg/kg/day (conventional CyA) and 3.3 mg/kg/day (CyA microemulsion) and did not change significantly during the study. The mean bioavailability of CyA from the microemulsion formulation was 23% higher than from conventional CyA. Replicate assessments indicated a more reproducible pharmacokinetic profile with CyA microemulsion. The overall incidence and nature of adverse events and changes in vital signs and laboratory variables were similar in both groups. No clinically relevant differences in efficacy were found between treatments. No loss of efficacy and no tolerability problems occurred after conversion from conventional to microemulsion CyA.

CONCLUSION

Existing CyA dosing guidelines, formulated for conventional CyA, are suitable for longterm CyA microemulsion therapy of patients with RA. These results indicate the pharmacokinetic advantages of the microemulsion formulation.

No pathogenic mutations in the persyn gene in Parkinson's disease

The persyn (gamma-synuclein) gene is highly homologous to the alpha-synuclein gene and is highly expressed in the nervous system. It is therefore, an excellent candidate gene for Parkinson's disease. However, we have sequenced the gene in a large number of families with parkinsonism and failed to find pathogenic mutations.

Final stage of maturation of the erythrocytic schizonts of rodent Plasmodium in the lungs

Schizonts of all rodent Plasmodium studied (Plasmodium yoelii, P. chabaudi, P. vinckei) show a characteristic morphology when they are completely mature: rounded or slightly elongate merozoites, completely detached from the pigment mass. At this stage, they are localized principally in the spleen and the lungs but, in impression smears of these organs they show two different aspects. In the spleen, schizonts are either inside the host erythrocyte or extraglobular but still close to a pigment mass; free merozoites are rare. In the lungs, on the contrary, merozoites are often free and dispersed; electron microscopy showed them to lie against the endothelium. Work by physiologists has shown the blood circulation in the alveoli to be much slowed down. Free merozoites, lined against the endothelium of relatively rigid capillaries, are in the best possible conditions to make contact with the intact red blood cells. Lungs appear to be the privileged site for the invasion of erythrocytes by the merozoites.

No evidence for radiation-induced clastogenic factors after in vitro or in vivo exposure of human blood

Experiments were performed with human plasma irradiated in vitro or in vivo in order to evaluate the extent to which clastogenic factors might disturb the adaptive response to DNA-damaging factors currently studied in our laboratory. The studies were carried out with plasma isolated from whole blood given 4 Gy of X-rays in vitro and with plasma from people receiving local radiotherapy at a total dose of about 60 Gy gamma rays. Addition of irradiated plasma to culture medium did not result in a statistically significant increase in structural aberrations in chromosomes of non-irradiated normal blood.

The very low density lipoprotein (VLDL) receptor is a genetic susceptibility factor for Alzheimer disease in a European Caucasian population

The epsilon4 allele of the apolipoprotein E gene (APOE) constitutes a major genetic susceptibility factor for Alzheimer disease (AD). Recently, a polymorphic triplet (CGG) in the very low density lipoprotein receptor (VLDL-R) gene, coding for a receptor binding only apoE-containing lipoproteins, was associated with AD in a Japanese population but not in Caucasian American populations. We explored this association and the potential interaction with the APOE polymorphism in a Caucasian sample of sporadic AD and control subjects of similar ages of European origin. The allelic distribution of the VLDL-R polymorphism differed significantly between Japanese and Caucasian populations (p < 0.0001). However, in our population, the presence of at least one VLDL-R 5 repeat allele increased significantly (p < 0.0003) the probability to develop AD after 65 years of age in APOE epsilon4 allele bearers.

[Spontaneous intraperitoneal rupture of the ureter]

An unusual case of spontaneous intraperitoneal rupture of the ureter was observed in adult with acute renal pain. Diagnosis was best established with CT rather than intravenous urography. CT demonstrated ureteral leakage with the contrast medium extravasating into the peritoneal cavity. The patient was initially managed successfully by endourology. Secondary stenosis of the ureter required surgery for partial resection of the distal ureter.

[Secondary prevention of coronary disease in France. Result of the EUROASPIRE study: the Lille register of ischemic cardiopathies]

The EUROASPIRE study was initiated to assess the impact of recommendations concerning secondary prevention of coronary artery disease in Europe published in 1994 by the European Societies of Cardiology, Hypertension and Atherosclerosis. France and eight other countries are involved in this project. The authors report the French data. A total of 546 men and women, aged less than 71, divided into 4 diagnostic groups (coronary bypass, angioplasty, myocardial infarction, acute ischaemia) were selected in different departments of cardiology. Data concerning their main risk factors and management were noted from the hospital files. At least 6 months after their hospital admission, 396 patients were systematically interrogated and examined. The availability of information on the risk factors in the hospital files varied according to the risk factor and diagnostic group from 61 to 97%. At the time of hospital admission, 42% of patients were considered to be smokers and 23% to be obese. Six months after hospital admission, 28% of patients were still smoking, 34% were obese, 49% had total cholesterol levels greater than 5.5 mmol/L (2.10 g/L) and 48% had blood pressure readings of over 140/90 mmHg. In France, as in other European countries, the prevalence of modulable risk factors of coronary artery disease is high at least 6 months after hospital admission. Systematic application of the recommendations of scientific societies should result in a significant decrease in recurrences and in mortality after an initial coronary event.

Polymorphism of the prion protein is associated with cognitive impairment in the elderly: the EVA study

BACKGROUND

Little is known about the role of the prion protein (PrP(sen)/gene PRNP). PRNP knockout mice studies suggest that PrP(sen) may be involved in CNS degeneration. This observation prompted us to examine the influence of PRNP genetic variability on cognitive abilities in the elderly.

METHODS

In a community-based sample of 1,163 subjects aged 59 to 71 years, we characterized the valine (Val) and methionine (Met) allele of the PRNP polymorphism at codon 129. The effect of this polymorphism was estimated on the Mini-Mental State Examination (MMSE) and on a global composite score built from a battery of nine different neuropsychological tests. The results were adjusted for age, gender, education, and apolipoprotein E (apoE) polymorphism.

RESULTS

Cognitive impairment (MMSE score < 24) was present in 2.5% of the Met-Met individuals, 2.9% of the Met-Val individuals, and 7.0% of Val-Val subjects (p = 0.02). Subjects homozygous for the PRNP Val allele had a lower MMSE and global score than the two other genotypes (p < 0.003). This effect was of the same magnitude as that of the apoE epsilon4 allele on cognitive performances. Both apoE epsilon4 and PRNP Val allelic effects were additive.

CONCLUSION

This observation suggests that variability of the PRNP locus may be associated with cognitive performance in the elderly. This result, if confirmed, offers potential clues for the role of PRNP in the human brain.

Chromosome alterations in breast carcinomas: frequent involvement of DNA losses including chromosomes 4q and 21q

Comparative genomic hybridization was applied to map DNA gains and losses in 39 invasive ductal breast carcinomas. Frequent abnormalities included gains on chromosomal regions 1q, 8q, 11q12-13, 16p, 19, 20q and X as well as frequent losses on 1p, 5q, 6q, 9p, 11q, 13q and 16q. Furthermore, frequent losses on 4q (20 cases) and 21q (14 cases) were found for the first time in this tumour type. High copy number amplifications were observed at 8q12-24, 11q11-13 and 20q13-ter. Highly differentiated tumours were associated with gains on 1q and 11q12-13 along with losses on 1p21-22, 4q, 13q, 11q21-ter. Undifferentiated breast carcinomas were characterized by additional DNA imbalances, i.e. deletions of 5q13-23, all of chromosome 9, the centromeric part of chromosome 13 including band 13q14 and the overrepresentation of chromosome X. We speculate that these changes are associated with tumour progression of invasive ductal breast cancer.

[Review on the use of CO2 in laparoscopy surgery]

Laparoscopic surgery is one of the treatment modalities available to urologists, who must be familiar with the concepts of the physiology of CO2 and its clinical consequences. CO2 is absorbed during insufflation, leading to hypercapnia, reaching a steady-state from the 20th minute. The insufflation pressure must be between 10 and 14 mmHg. Intraoperative surveillance is based on oxygen saturation (pulse oximeter) and capnography, which measures the CO2 concentration of expired air. The causes of hypercapnia must be prevented: untimely recovery, retroperitoneal dissection, excessive intra-abdominal pressure. If hypercapnia occurs, the patient must be exsufflated and the operation should be resumed after a certain interval. The specific complications of laparoscopy (gas embolism, arrhythmias, pneumothorax) can be avoided by respecting the rules of security and by maintaining surveillance during recovery. The pain due to diaphragmatic peritoneal irritation can also be decreased by complete exsufflation.

Lymph node metastases: safety and effectiveness of MR imaging with ultrasmall superparamagnetic iron oxide particles--initial clinical experience

PURPOSE

To evaluate the clinical and biologic safety of ultrasmall superparamagnetic iron oxide particles (AMI-227) as a contrast agent for magnetic resonance (MR) lymphography and to assess their efficacy for the differentiation of metastatic and benign nodes in patients with urologic and pelvic cancer.

MATERIALS AND METHODS

Thirty adults suspected of having lymph node metastases underwent MR imaging before and 22-26 hours after intravenous infusion of AMI-227 (1.7 mg Fe/kg). Sixty histopathologically proved lymph nodes were analyzed on MR images, and 29 of these nodes were also analyzed quantitatively.

RESULTS

AMI-227 was well tolerated with no major side effects. It allowed the detection of 10 additional nodes relative to those detected at MR imaging without AMI-227. None of the 27 metastatic nodes showed a decrease in signal intensity (SI) on AMI-227-enhanced images; nine of 27 metastatic nodes showed an increase in SI on T1-weighted images, probably resulting from altered capillary permeability in the tumor. A visually perceptible reduction in SI, indicating active AMI-227 uptake, was observed on postcontrast T2- and T2*-weighted images in 16 of 21 benign nodes. The SI ratio of benign nodes was lower than that of metastatic nodes on T2- and T2*-weighted images. The sensitivity of AMI-227-enhanced MR lymphography was 100%, and the specificity was 80%.

CONCLUSION

AMI-227 is safe and may facilitate the differentiation of metastatic and benign nodes in patients with urologic and pelvic cancers.

Origin of human chromosome 21 and its consequences: a 50-million-year-old story

Great apes (Pongidae) possess a chromosome similar to human chromosome 21 (HSA21), whose trisomy was described in both chimpanzee and orangutan. Having studied more than 200 mammalian species by chromosome banding techniques and reconstructed Primates phylogeny, we reinvestigated, using fluorescence in situ hybridization, primate and non-primate mammals that we considered to possess a karyotype representative of their taxonomic group. DNA sequences from HSA21 and human chromosome 3 (HSA3) are synthenic and form a large and similar chromosome in species from distinct orders, such as Primates, Carnivora, Artiodactyla and Scandentia. In Primates, this syntheny was maintained in lemurs and was disrupted by a fission in Old World monkeys (catarrhines). Another fission occurred in New World monkeys (platyrrhines), conserving a syntheny between HSA21 and a very short segment of HSA3 DNA sequences. Thus, the ancestral HSA21 was formed after the divergence between platyrrhines and catarrhines and before the emergence of Cercopithecidae. This exposed the human and Pongidae ancestry to trisomy 21 for a period of 30-50 million years, while, in other catarrhines, the equivalent of HSA21 was further involved in various translocations forming large chromosomes whose aneuploidy, very probably incompatible with life, protected them against trisomy 21.

[Renal tumor with thrombus involving all of the lumen of the inferior vena cava: surgical indication, technique and results]

OBJECTIVES

Almost 5% of renal tumours are associated with thrombus of the renal vein or inferior vena cava at the time of diagnosis. Radical nephrectomy with complete resection of the tumour nodule is the reference first-line treatment in this situation. This retrospective series was designed to analyse the surgical strategy according to the extent of the tumour nodule and the morbidity and mortality as a function of the prognostic factors of these renal tumours.

MATERIALS AND METHODS

From 1982 to 1995, 51 patients (out of a series of 724 nephrectomies) presented with renal vein invasion involving all of the lumen of the inferior vena cava. The choice of medical imaging varied over time (cavography, Doppler ultrasound, CT, MRI and transoesophageal ultrasonography). Control of the inferior vena cava was always performed below the renal veins and above the thrombus.

RESULTS

MRI and transoesophageal ultrasonography were found to be the most reliable diagnostic examinations. The incision and vessel control technique must be selected as a function of the type of thrombus and the emboligenic risk. With a follow-up of 4.3 years, the overall 2-year survival was 46% and the 5-year survival was 31%. All recurrences at 1 year occurred in N+ patients.

CONCLUSION

Lymph node status and invasion of the perirenal fat are the most important prognostic factors, while the presence and length of the thrombus do not appear to influence survival. Radical nephrectomy of these tumours, invading all of the lumen of the inferior vena cava, requires complete resection of the thrombus. Adhesion of the thrombus constitutes a major technical problem that must be envisaged before the incision in order to correctly control the vessels.

High-level secretion of biologically active recombinant porcine follicle-stimulating hormone by the methylotrophic yeast Pichia pastoris

An active recombinant glycoprotein hormone, porcine follicle-stimulating hormone (recFSH), has been produced for the first time in the methylotrophic yeast, Pichia pastoris. The yield of secreted recFSH (10 mg/l) was the highest ever reached. RecFSH displayed an apparent molecular mass of 41 kDa by SDS-PAGE and was found to bear only N-linked carbohydrates of the high-mannose type. Its in vitro binding and cell-stimulating activities were identical to those of pituitary porcine FSH. The large availability and the noncharged N-glycans of FSHrec should render it highly valuable for structural studies.

Perirenal textiloma: MR and serial CT appearance

We describe changes in imaging features of a textiloma (retained surgical sponge or retained foreign body) left in the renal fossa after exploratory renal surgery. One year after the initial surgery, the MR aspect of the textiloma was not specific, with a homogeneous low signal intensity on T1-weighted images. Serial CT examinations over 4 years demonstrated progressive growth and calcification of the mass which appeared pseudocystic with a peripheral inflammatory wall. Granulomas caused by a retained surgical sponge should be considered as a cause of retroperitoneal mass in patients with a history of prior surgery.

Health-related quality of life associated with lower urinary tract symptoms in four countries

OBJECTIVES

To describe health-related quality of life (HRQL) associated with lower urinary tract symptoms (LUTS) assessed by validated questionnaires in four countries.

METHODS

More than 6000 men, recruited by using community- or population-based sampling in four countries, completed questionnaires soliciting information about urinary symptom frequency, bother, degree of interference with daily activities, and other measures of HRQL.

RESULTS

In all countries, disease-specific HRQL worsened with increasing age. Adjusting for age, most disease-specific HRQL measures were significantly worse with increasing symptom severity. The correlation between symptoms and HRQL was strongest in countries with higher prevalence of symptoms, such as Japan or the United States, and less pronounced in countries with lower prevalence (France, Scotland), possibly reflecting the lower variability in scores.

CONCLUSIONS

HRQL measures are worse in older men, and increased urinary symptom severity is associated with worse disease-specific HRQL in all countries, despite potential cross-cultural differences in disease prevalence, medication use, perceptions, or willingness to report symptoms or worse HRQL. This cross-cultural consistency suggests that an assessment of symptom bother or interference with daily activities may be useful in patient evaluation.

Emergence of a brain-expressed variant melanin-concentrating hormone gene during higher primate evolution: a gene "in search of a function"

Two related but distinct melanin-concentrating hormone (MCH) gene systems, i.e., the authentic and variant genes, have been characterized in the human, while only a single MCH gene has been found in the rat. We previously established that the variant gene corresponds to exon-I-deleted copies of the authentic gene mapped on chromosomes 5 and 12, respectively. In this report, we examined the expression of the authentic and variant MCH genes in the human brain. Mature mRNAs of the authentic MCH gene appeared to be predominantly expressed in the hypothalamus, whereas putative unprocessed transcripts of the variant MCH gene were found in other brain areas but not in the hypothalamus. Several products of the variant MCH gene were identified by RACE-PCR in the fetal human brain. One of these transcripts encoded a putative protein of 72 amino acids, while another transcript may potentially generate a protein of 35 amino acids. Thereafter, we explored the question of MCH gene transposition during Primate evolution. Southern blotting, PCR analyses using several genomic DNAs of Primates, and in situ hybridization on metaphase chromosomes led us to define at least three types of genetic events associated with the emergence of the variant MCH gene: (1) translocation of an exon II-exon III copy of the authentic MCH gene onto the equivalent of the human chromosome 5p arm of Anthropoidea ancestors (between 25 and 55 MYA); (2) exon II truncation and mutations before divergence of the Hylobatidae (about 15 MYA); and (3) duplication of the variant gene on the equivalent of the human chromosome 5p and 5q arms in the Hominidae, i.e., 5-10 MYA. Taken together, these results support the hypothesis that transposition/gene rearrangement processes could underlie the evolutionary emergence of new MCH-related genes expressed differentially in the brains of higher Primates, illustrating the concept of genes "in search of function" instead of true "pseudogenes."