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At least 199 records · Page 11Linked to original sources
PubMed1996

Paternity after unilateral cryptorchidism: a controlled study.

OBJECTIVE: To determine if paternity is decreased among formerly unilateral cryptorchid men compared with a control group of men. SUBJECTS AND METHODS: Formerly unilateral cryptorchid men who had orchiopexy between 1955 and 1971 at the Children's Hospital of Pittsburgh and a group of control men have had their medical records reviewed and have been surveyed by questionnaire. RESULTS: Among the men who had ever married and had attempted paternity, significantly more of the unilateral cryptorchid men had been unable to father children (10.5%) than among the control group (5.4%). No difference was found when the groups were compared for the duration of regular intercourse without contraception to conception of their first child. There was no relationship between the age of orchiopexy or lifestyle factors and paternity or between the age of orchiopexy and months of regular unprotected intercourse to conception. Paternity among both groups was related to female-related infertility factors and to the presence of varicoceles. CONCLUSION: When compared with a control group, paternity was compromised after unilateral cryptorchidism. Infertility is about twice as frequent among the unilateral group. There was no evidence of subfertility requiring a longer exposure of regular intercourse without contraception among the fertile subgroup. No correlation was found between age of orchiopexy and paternity.

Adult↗
PubMed2026

Beckwith-Wiedemann spectrum exhibiting a 46,XY karyotype caused by genome-wide paternal uniparental heterodisomy: a case report.

BACKGROUNDS: Patients with genome-wide paternal uniparental disomy (GWpUPD) usually exhibit clinical features of Beckwith-Wiedemann syndrome (BWS) and a 46,XX karyotype, with all chromosomes showing isodisomy. To date, male patients with GWpUPD and a complete 46,XY karyotype, specifically involving heterodisomy, have not been described. RESULTS: We report a male infant exhibiting classical BWS clinical features. DNA methylation analyses showed paternal-specific methylation across multiple imprinted loci, suggesting GWpUPD. Genetic analysis of autosomes and sex chromosomes indicated two distinct paternal genomes in peripheral blood leukocytes, whereas a normal biparental genome was detected in other tissues under chimeric conditions. These findings indicated that the patient had genome-wide paternal uniparental heterodisomy (GWpUPhD). The SNP array revealed the presence of one copy of the X chromosome and one copy of the Y chromosome, the patient is a chimera composed of 46,XY biparental cells (with maternal X) and 46,XY GWpUPhD cells (with paternal X). CONCLUSIONS: This is the first report of a male patient with a GWpUPhD chimera. We propose a potential mechanism of GWpUPhD formation. Our findings expand the molecular spectrum of GWpUPD and provide valuable insights into its pathogenesis in chimeric conditions. Furthermore, the potential for clinical manifestations unique to 46,XY heterodisomy warrants careful long-term follow-up.

Humans↗
PubMed1997

Paternal transcripts for glucose-6-phosphate dehydrogenase and adenosine deaminase are first detectable in the human preimplantation embryo at the three- to four-cell stage.

The transition between dependence on maternal transcripts and proteins inherited in the oocyte and embryonic gene expression in the human preimplantation embryo occurs at the four- to eight-cell stage. Recently, studies using reverse transcriptase polymerase chain reaction (RT-PCR) have detected paternal transcripts for the Y-linked genes, ZFY and SRY, and the myotonic dystrophy associated protein kinase gene, DK, as early as the late pronucleate one-cell stage. However, expression at the protein level has not been demonstrated and its function at these early stages is unknown. Using coding sequence polymorphisms to distinguish maternal and paternal transcripts, we have examined the transcription of two ubiquitously expressed genes: X-linked glucose-6-phosphate dehydrogenase (G6PD) and adenosine deaminase (ADA). Both G6PD and ADA are housekeeping genes with TATA-less promoters which, because of their roles in metabolism and ubiquitous expression, may provide a more reliable indication of the timing of activation of the embryonic genome. They also each have biallelic polymorphisms with a high heterozygosity ratio which can be detected by restriction digestion. Couples undergoing in vitro fertilization (IVF) were screened for these polymorphisms. Individual spare oocytes and embryos at different stages of preimplantation development were analyzed by RT-PCR and appropriate restriction digestion in those cases in which the male partner carried a different allele to the female partner. In addition, since only female embryos inherit the paternal allele of X-linked G6PD, cDNA was also analyzed for ZFX/ZFY transcripts to identify the sex of each embryo. One hundred and twenty three individual oocytes and embryos were analyzed by RT-PCR and restriction digestion to detect the paternal transcripts from the polymorphic alleles. Maternal transcripts for G6PD, ADA, and ZFX were detected in all oocytes and embryos and at all stages. Following restriction digestion, paternal G6PD and ZFY transcripts were first detected at the four-cell stage and paternal ADA transcripts in an embryo at the three-cell stage coinciding with the onset of dependency on transcription from the embryonic genome. This approach should be widely applicable to other genes since similar polymorphisms exist in the coding regions of many genes.

Adenosine Deaminase↗
PubMed2000

Search for imprinted regions on chromosome 14: comparison of maternal and paternal UPD cases with cases of chromosome 14 deletion.

Over the past few years, regions of genomic imprinting have been identified on a small number of chromosomes through a search for the etiology of various disorders. Distinct phenotypes have been associated with both maternal and paternal uniparental disomy (UPD) for chromosome 14. This observation indicates that there are imprinted genes present on chromosome 14, although none have been identified to date. In order to focus the search for imprinted genes on chromosome 14, we analyzed cases of maternal and paternal UPD 14 and compared them with cases of chromosome 14 deletions. Cases of paternal UPD were compared with maternal deletions and maternal UPD compared with paternal deletions. The paternal UPD anomalies seen in maternal deletion cases allowed us to associate the following features and chromosomal regions: Hirsute forehead: del(14)(q12q13. 3) and del(14)(q32); blepharophimosis: del(14)(q32); small thorax: del(14)(q11.2q13); and joint contractures: del(14)(q11.2q13) and del(14)(q31). Comparison of maternal UPD and paternal deletion cases revealed fleshy nasal tip to be most often associated with del(14)(q32), scoliosis with del(14) (q23q24.2), and del(14)(q32. 11qter) and small size at birth to be associated with del(14)(q11q13) and del(14)(q32). Our study, in conjunction with a prior study of UPD 14 and partial trisomy 14 cases, and what is known of imprinting in regions of mouse chromosomes homologous to human chromosome 14, leads us to conclude that 14q23-q32 is likely an area where imprinted genes may reside.

Abnormalities, Multiple↗
PubMed2000

Sexual selection and the evolution of exclusive paternal care in arthropods.

Internal fertilization and anisogamy are thought to impede the evolution of exclusive paternal care by reducing paternity assurance and increasing male promiscuity. The potential role of sexual selection in easing these constraints is currently being examined in vertebrates but has not been seriously studied in most arthropods. To distinguish the effects of sexual from natural selection on the evolution of arthropod paternal care, I tested predictions of the state of several life history and behavioural traits under both forms of selection across all known taxa with exclusive paternal care. The results suggest parallels between prezygotic nuptial gifts and exclusive postzygotic paternal care and support the hypothesis that, in arthropods, male behaviours that enhance female reproductive success either directly by releasing females from the fecundity constraints of maternal care (enhanced fecundity hypothesis) or indirectly by identifying mates with superior genes (handicap principle) are traits on which sexual selection has acted. Under such conditions males willing to guard young become preferred mates for gravid females and enjoy greater promiscuity than males unable or unwilling to guard. Females use nest construction or the act of guarding another female's eggs as honest signals of paternal intent and quality. Copyright 2000 The Association for the Study of Animal Behaviour.

Journal Article↗
PubMed1993

Requirements for promoter activity in mouse oocytes and embryos distinguish paternal pronuclei from maternal and zygotic nuclei.

Fertilization of mouse eggs produces a 1-cell embryo containing both a paternal and maternal pronucleus. These two nuclei combine during the first mitosis to form the zygotic nuclei of 2-cell embryos. This transition is accompanied by the onset of transcription and the decline of maternal mRNA-dependent gene expression. To determine how changes in nuclear composition affect gene expression, plasmid DNA containing a promoter and an enhancer that function throughout a broad host range was injected into nuclei of oocytes and embryos. The requirements for promoter activity in paternal pronuclei of 1-cell embryos were distinct from those in maternal or zygotic nuclei: (1) Paternal pronuclei permitted high levels of promoter activity relative to maternal or zygotic nuclei. (2) Butyrate, an agent that alters chromatin structure, stimulated promoter activity in maternal or zygotic nuclei, but not in paternal pronuclei. (3) The embryo-responsive polyomavirus F101 enhancer also stimulated promoter activity, but only after formation of a 2-cell embryo. Either butyrate or the F101 enhancer stimulated promoter activity in zygotic nuclei to the level observed in paternal pronuclei. Stimulation also was observed with 2-cell embryos containing nuclei of only maternal or paternal origin, but their transcriptional capacity was more limited. These and other results support the hypothesis that the need for enhancers in 2-cell embryos results from repression by chromatin structure, and the role of enhancers is to relieve this repression.

Animals↗
PubMed1993

Transfer of paternal mitochondrial DNA during fertilization of honeybee (Apis mellifera L.) eggs.

Strict maternal inheritance of mitochondrial (mt) DNA is believed to be the rule in most eukaryotic organisms because of exclusion of paternal mitochondria from the egg cytoplasm during fertilization. In honeybees, polyspermic fertilization occurs, and many spermatozoa, including their mitochondria-rich flagellum, can completely penetrate the egg, thus allowing for a possibly high paternal leakage. In order to identify paternal mtDNA in honeybee eggs, restriction fragment length polymorphisms (RFLP) of different subspecies were used. Total DNA extracts of different developmental stages of an Apis mellifera carnica x Apis mellifera capensis hybrid brood were tested with a radioactively-labelled diagnostic mtDNA probe. Densitograms of autoradiographs indicated that the male contribution represents up to 27% of the total mitochondrial DNA in the fertilized eggs 12 h after oviposition. In subsequent developmental stages the portion of paternal mtDNA slowly decreased until hatching of the larvae when only traces were found. Although rapid disintegration of paternal mtDNA does not occur, the initially high paternal mitochondrial contribution is not maintained in the adult animal.

Animals↗
PubMed1983

Transcripts of paternal and maternal actin gene alleles are present in interspecific sea urchin embryo hybrids.

Analysis of actin-coding RNAs in interspecific hybrid sea urchin embryos of Strongylocentrotus purpuratus and Lytechinus variegatus, and S. purpuratus and S. droebachienis has revealed the presence of transcripts from both paternal and maternal S. purpuratus actin gene alleles. In the L. variegatus female X S. purpuratus male embryos transcripts from at least two different paternal actin gene alleles are present in both the blastula and prism stages. In the reciprocal S. purpuratus female X L. variegatus male embryos, the same two maternal (S. purpuratus) alleles were also expressed as RNA in blastula. The S. droebachiensis female X S. purpuratus male embryos appear to contain transcripts from at least one paternal actin gene allele at the blastula stage. The paternally derived actin-coding RNAs are the same size as the mature actin mRNAs expressed in normal S. purpuratus embryos. Since all known S. purpuratus actin genes contain at least two introns, the paternal alleles are not only transcribed in the hybrid embryos, but also the primary transcripts are probably processed to mature mRNA. An explanation of the diversity of observations in the literature on paternal genome expression in hybrid sea urchin embryos is discussed.

Actins↗
PubMed2006

Numerical chromosome anomalies detected in paternally derived pronuclei of tripronuclear zygotes after intracytoplasmic sperm injection.

OBJECTIVE: To investigate after intracytoplasmic sperm injection (ICSI) the paternal-derived pronuclei of zygotes with three pronuclei (3PN) for numerical-chromosome anomalies by using fluorescence in situ hybridization. DESIGN: A total of 211 ICSI 3PN zygotes have been analyzed for numerical-chromosome anomalies in paternally derived pronuclei and compared with the group of 82 zygotes originated during IVF. In the ICSI group, 163 zygotes were evaluated for numerical-chromosome anomalies by using DNA probes for chromosomes 18, X, and Y, and 48 zygotes, for chromosomes 21, X, and Y. In the IVF group, 68 zygotes were evaluated for numerical-chromosome anomalies by using probes for chromosomes 18, X, and Y, and 14 zygotes, by using chromosomes 21, X, and Y. SETTING AND PATIENT(S): Tripronuclear zygotes were obtained from 74 and 176 patients participating in IVF and ICSI treatment cycles at a university hospital in Switzerland. INTERVENTION(S): To evaluate the frequency of numerical-chromosome anomalies in different populations of infertile patients, a total of 211 ICSI zygotes were divided into three groups of zygotes from men with oligozoospermia (n = 124), severe oligozoospermia (n = 53), and azoospermia (n = 34). MAIN OUTCOME MEASURE(S): Incidence of sex-chromosome aneuploidy, diploidy, and aneuploidy for chromosomes 18 or 21. RESULT(S): Overall incidence of numerical-chromosome anomalies in paternal-derived pronuclei after ICSI (9.5%) was significantly higher than the rate found in paternal-derived pronuclei of IVF zygotes (1.2%). Among ICSI zygotes, sex-chromosome aneuploidy (5.2%) and diploidy (2.8%) were two dominant numerical anomalies in paternal-derived pronuclei. In contrast, aneuploidy for autosomes 18 or 21 was not significantly different when comparing ICSI with IVF zygotes. Regarding different groups of infertile patients, the highest incidence of numerical-chromosome anomalies was found in zygotes originating from men with severe oligozoospermia (13.2%), followed by those originating from men with azoospermia (8.8%) and oligozoospermia (8.1%). CONCLUSION(S): Sex-chromosome aneuploidy and diploidy were the most frequent numerical-chromosome anomalies found in paternal pronuclei of ICSI 3PN zygotes. Surprisingly, no statistically significant difference in the incidence of numerical-chromosome anomalies was observed in the three groups of pronuclei derived from men with oligozoospermia, severe oligozoospermia, and azoospermia.

Adult↗
PubMed1998

Single paternity of clutches and sperm storage in the promiscuous green turtle (Chelonia mydas).

Paternity of 22 green turtle (Chelonia mydas) clutches from 13 females of the southern Great Barrier Reef breeding population was determined through microsatellite analyses at five loci, including the analysis of successive clutches for nine of the females. A large number of alleles per locus (10-40) provided probabilities of detecting multiple paternity that were quite high, particularly at all loci combined (99.9%). Although green turtles are promiscuous breeders and there was an expectation of finding extensive multiple paternity, only two clutches were multiply sired and, in these, very few eggs had been fertilized by a secondary male. The rarity of multiple paternity may reflect either a low proportion of multiple matings by females in this population, or sperm competition, possibly resulting from a first-male sperm preference. Additionally, the analysis of > 900 offspring provided data on mutations, which included 20 mutation events that were observed in 27 offspring and involved both maternal and paternal lineages. Most mutations (n = 16) occurred at a single highly variable locus and their presence emphasizes the need to use multiple loci in paternity studies.

Animals↗
PubMed2003

Pollen flow in the wildservice tree, Sorbus torminalis (L.) Crantz. I. Evaluating the paternity analysis procedure in continuous populations.

The joint development of polymorphic molecular markers and paternity analysis methods provides new approaches to investigate ongoing patterns of pollen flow in natural plant populations. However, paternity studies are hindered by false paternity assignment and the nondetection of true fathers. To gauge the risk of these two types of errors, we performed a simulation study to investigate the impact on paternity analysis of: (i) the assumed values for the size of the breeding male population (NBMP), and (ii) the rate of scoring error in genotype assessment. Our simulations were based on microsatellite data obtained from a natural population of the entomophilous wild service tree, Sorbus torminalis (L.) Crantz. We show that an accurate estimate of NBMP is required to minimize both types of errors, and we assess the reliability of a technique used to estimate NBMP based on parent-offspring genetic data. We then show that scoring errors in genotype assessment only slightly affect the assessment of paternity relationships, and conclude that it is generally better to neglect the scoring error rate in paternity analyses within a nonisolated population.

Computer Simulation↗
PubMed2000

Paternal origin of FGFR2 mutations in sporadic cases of Crouzon syndrome and Pfeiffer syndrome.

Crouzon syndrome and Pfeiffer syndrome are both autosomal dominant craniosynostotic disorders that can be caused by mutations in the fibroblast growth factor receptor 2 (FGFR2) gene. To determine the parental origin of these FGFR2 mutations, the amplification refractory mutation system (ARMS) was used. ARMS PCR primers were developed to recognize polymorphisms that could distinguish maternal and paternal alleles. A total of 4,374 bases between introns IIIa and 11 of the FGFR2 gene were sequenced and were assayed by heteroduplex analysis, to identify polymorphisms. Two polymorphisms (1333TA/TATA and 2710 C/T) were found and were used with two previously described polymorphisms, to screen a total of 41 families. Twenty-two of these families were shown to be informative (11 for Crouzon syndrome and 11 for Pfeiffer syndrome). Eleven different mutations in the 22 families were detected by either restriction digest or allele-specific oligonucleotide hybridization of ARMS PCR products. We molecularly proved the origin of these different mutations to be paternal for all informative cases analyzed (P=2. 4x10-7; 95% confidence limits 87%-100%). Advanced paternal age was noted for the fathers of patients with Crouzon syndrome or Pfeiffer syndrome, compared with the fathers of control individuals (34. 50+/-7.65 years vs. 30.45+/-1.28 years, P<.01). Our data on advanced paternal age corroborates and extends previous clinical evidence based on statistical analyses as well as additional reports of advanced paternal age associated with paternal origin of three sporadic mutations causing Apert syndrome (FGFR2) and achondroplasia (FGFR3). Our results suggest that older men either have accumulated or are more susceptible to a variety of germline mutations.

Acrocephalosyndactylia↗
PubMed1997

Paternal X-chromosome inactivation in human trophoblastic cells.

Dosage compensation for X-chromosome-linked genes between male and female mammals occurs by inactivation of one of the two X chromosomes in the female. In somatic cells, either the paternal or the maternal X chromosome is randomly inactivated in a given cell. In contrast, in the extra-embryonic tissues of mice, the paternally-derived X chromosome is preferentially inactivated. The evidence for paternal X-chromosome inactivation in humans is controversial and remains to be clarified. In this study, we have developed a sensitive polymerase chain reaction (PCR) technique to investigate the methylation pattern of the X-linked androgen receptor (AR) gene. The 5' CpG island of this gene is methylated on the inactive X chromosome and hypomethylated on the active X chromosome in somatic cells. The paternal and the maternal alleles of the AR gene may be distinguished by a polymorphism in the number of CAG triplet repeats within the CpG island. As a source of human extra-embryonic tissue, we used chorionic villus (CV) samples from female conceptuses of 10-12 weeks gestation. From a tiny branch of a CV sample, two distinct cell lineages, the trophoblastic and mesodermal lineages, were dissected apart by trypsin digestion and micromanipulation and DNA was extracted separately from these purified tissues. Digestion of the DNA with the methylation-sensitive restriction enzyme, Hpall, followed by PCR amplification revealed that the paternal allele is preferentially methylated in trophoblastic cells, but not in mesodermal cells. These results strongly suggest that the paternal X chromosome is preferentially inactivated in the human extra-embryonic tissues early in development.

Animals↗
PubMed1992

Influence of paternal characteristics on the risk of low birth weight.

The combined effects of maternal and paternal factors on the risk of delivering low birth weight (less than 2,500 g) and very low birth weight (less than 1,500 g) infants were examined among married parents. Using 1984-1988 natality data compiled by the National Center for Health Statistics, the authors found paternal education and race to have independent effects on the risks of low birth weight and very low birth weight after adjustment for maternal characteristics. The odds of low and very low birth weight decreased with increasing paternal education. Adjustment for paternal education decreased the effect of maternal education on the risks of low and very low birth weight. Additionally, the examination of paternal race led to the identification of a subgroup of married black women with lower risks of low and very low birth weight than married black mothers overall. These data suggest that paternal characteristics should be used, in addition to maternal characteristics, to describe the risks of low and very low birth weight.

Adult↗
PubMed2001

Mate guarding in the Seychelles warbler is energetically costly and adjusted to paternity risk.

Males may increase their fitness through extra-pair copulations (copulations outside the pair bond) that result in extra-pair fertilizations, but also risk lost paternity when they leave their own mate unguarded. The fitness costs of cuckoldry for Seychelles warblers (Acrocephalus sechellensis) are considerable because warblers have a single-egg clutch and, given the short breeding season, no time for a successful replacement clutch. Neighbouring males are the primary threat to a male's genetic paternity. Males minimize their loss of paternity by guarding their mates to prevent them from having extra-pair copulations during their fertile period. Here, I provide experimental evidence that mate-guarding behaviour is energetically costly and that the expression of this trade-off is adjusted to paternity risk (local male density). Free-living males that were induced to reduce mate guarding spent significantly more time foraging and gained significantly better body condition than control males. The larger the reduction in mate guarding, the more pronounced was the increase in foraging and body condition (accounting for food availability). An experimental increase in paternity risk resulted in an increase in mate-guarding intensity and a decrease in foraging and body condition, and vice versa. This is examined using both cross-sectional and longitudinal data. This study on the Seychelles warbler offers experimental evidence that mate guarding is energetically costly and adjusted to paternity risk.

Animals↗
PubMed1993

Treatment of recurrent spontaneous abortion by immunization with paternal lymphocytes: results of a controlled trial.

PROBLEM: It remains unclear whether maternal immunization with paternal lymphocytes prior to conception improves the reproductive outcome in women with recurrent abortion in whom all secondary causes have been excluded. METHOD: A double-blind placebo controlled trial was instituted in women with unexplained recurrent spontaneous abortion, comparing immunization with 400 million paternal to 400 million maternal (autologous) lymphocytes. The groups were compared in a paired sequential trials chart, by logistic regression, and, in addition, a meta-analysis of this and other published trials was carried out. RESULTS: The live birth rate among pregnancies in paired couples with paternal lymphocyte immunization was 68% compared to 47% in the women who received their own cells. The results bordered on, but did not achieve, statistical significance. The women in each group were thoroughly investigated to exclude known causes of recurrent pregnancy loss and appeared to have been well matched in all variables. Women with lymphocytotoxic antibodies against paternal lymphocytes were excluded. Unlike our previous study there was not association between the time to conception and the chance of a successful outcome. Indeed, the time to conception was relatively short, 12 wk in all groups. The meta-analysis supported an overall modest favorable experience with paternal cells. CONCLUSION: The study is consistent with a general trend favoring paternal over maternal lymphocyte immunization but reinforces the need for larger multicenter controlled trials as well as more detailed biological study in humans to understand the nature of the maternal-fetal interface and its breakdown.

Abortion, Habitual↗
PubMed2005

Dynamic paternity allocation as a function of male plumage color in barn swallows.

Paternity in male animals can be influenced by their phenotypic signals of quality. Accordingly, the behavior underlying patterns of paternity should be flexible as signals of quality change. To evaluate the dynamics of paternity allocation, we analyzed paternity before and after manipulating plumage coloration, a known signal of quality, in male barn swallows Hirundo rustica. We found that, in successive breeding bouts, only males whose plumage color was experimentally enhanced received greater paternity from their social mates, demonstrating evidence for flexible and dynamic paternity allocation and the importance for males of maintaining signals of quality well after pair bond formation.

Animals↗
PubMed1993

Dynamic mutation in Dutch Huntington's disease patients: increased paternal repeat instability extending to within the normal size range.

Analysis of the distribution of normal and expanded alleles of the polymorphic (CAG)n repeat in the IT15 gene in the Dutch population confirmed the presence of an expanded repeat on all Huntington's disease (HD) chromosomes. Our results show that the size distributions of normal and affected alleles overlap. Normal alleles range from 11 to 37 repeats and HD alleles contain 37 to 84 repeats. A clear correlation is found between age at onset and repeat length, but the spread of the age at onset in the major repeat range producing characteristic HD is too wide to be of diagnostic value. In the available parent-offspring pairs, maternal HD alleles show a moderate instability with a slight preponderance of size increase over size decrease. Paternal alleles have a bimodal distribution: the majority (69%) behave similarly to the maternal alleles, while the remainder (31%) show a dramatic expansion, the degree of which appears proportional to the initial size. This is shown in three out of four juvenile patients, who have repeats of 71, 74, and 84 copies, respectively, originating from expanded paternal HD alleles in the previous generation. Two sporadic cases are caused by expansion of 'large' normal paternal alleles of 32 and 34 repeats, respectively, to 46 copies. This not only confirms the diagnosis of HD in two de novo cases, but it also underlines the increased paternal instability. In addition paternal repeat instability was once detected within the normal range in two sibs who inherited 21 and 22 repeats, respectively, on the same paternal chromosome. In two Dutch HD families the segregation of the expanded (CAG)n repeat was found. Analysis of the (CAG)n repeat in our previously reported recombinants confirmed their disease status.

Adult↗