RESUMO
Introduction: Before the COVID-19 public health emergency, few genetics providers used telehealth. As a response to this, many genetics providers began conducting telehealth care, referred to as telegenetics, usually with guidance from their institutions but without specific guidance related to the uniqueness of genetic services. Objectives: The Telegenetics Workgroup of the National Coordinating Center for Regional Genetics Networks convened a panel of experts in the fields of telemedicine, genetics, and genomics to review the existing literature on telegenetics and synthesize best operating practices for medical geneticists, genetic counselors, and metabolic dietitians providing telegenetics services. Methods: The group searched PubMed using the terms "telegenetics," "telemedicine + genetics," and "telehealth + genetics." The group also reviewed the Northeast Telehealth Resource Center's telegenetics webliography. Websites were searched, including the American Telemedicine Association's website, Center for Connected Health Policy, and National Telehealth Resource Center for position statements, standards documents, and guidelines. The group met frequently by videoconference and discussed the literature, and using expert consensus, the group determined best practices in providing telegenetics services. Results: These telegenetics best practices cover important aspects of telegenetics services, including, but not limited to, ongoing delivery of telegenetics services, use of special technology, legal and regulatory requirements, and considerations regarding special settings and circumstances in which telegenetics may be conducted. Conclusions: Recognizing the growing use of telegenetics and a future in which telegenetics continues to be part of the regular practice of genetics, this guide informs genetics providers of best practices for delivering telegenetics services to patients.
Assuntos
COVID-19 , Pandemias , SARS-CoV-2 , Telemedicina , Humanos , Telemedicina/organização & administração , SARS-CoV-2/genética , Serviços em Genética/organização & administração , Infecções por Coronavirus/epidemiologia , Guias de Prática Clínica como Assunto , Pneumonia Viral/epidemiologia , Estados Unidos , Betacoronavirus/genéticaRESUMO
During the Centers for Disease Control and Prevention's Zika Virus Response, birth defects surveillance programs adapted to monitor birth defects potentially related to Zika virus (ZIKV) infection during pregnancy. Pregnancy outcomes occurring during January 2016 to June 2017 in 22 U.S. states and territories were used to estimate the prevalence of those brain and eye defects potentially related to ZIKV. Jurisdictions were divided into three groups: areas with widespread ZIKV transmission, areas with limited local ZIKV transmission, and areas without local ZIKV transmission. Prevalence estimates for selected brain and eye defects and microcephaly per 10,000 live births were estimated. Prevalence ratios (PRs) and 95% confidence intervals (CIs) were estimated using Poisson regression for areas with widespread and limited ZIKV transmission compared with areas without local ZIKV transmission. Defects with significantly higher prevalence in areas of widespread transmission were pooled, and PRs were calculated by quarter, comparing subsequent quarters to the first quarter (January-March 2016). Nine defects had significantly higher prevalence in areas of widespread transmission. The highest PRs were seen in intracranial calcifications (PR = 12.6, 95% CI [7.4, 21.3]), chorioretinal abnormalities (12.5 [7.1, 22.3]), brainstem abnormalities (9.3 [4.7, 18.4]), and cerebral/cortical atrophy (6.7 [4.2, 10.8]). The PR of the nine pooled defects was significantly higher in three quarters in areas with widespread transmission. The largest difference in prevalence was observed for defects consistently reported in infants with congenital ZIKV infection. Birth defects surveillance programs could consider monitoring a subset of birth defects potentially related to ZIKV in pregnancy.
Assuntos
Anormalidades Congênitas , Anormalidades do Olho , Complicações Infecciosas na Gravidez , Infecção por Zika virus , Zika virus , Encéfalo/anormalidades , Encéfalo/virologia , Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/virologia , Anormalidades do Olho/epidemiologia , Anormalidades do Olho/virologia , Feminino , Humanos , Lactente , Microcefalia , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Prevalência , Infecção por Zika virus/complicações , Infecção por Zika virus/congênito , Infecção por Zika virus/epidemiologiaRESUMO
As diverse racial and ethnic minority populations continue to grow in the United States, the racial and ethnic diversity of the genetics workforce has remained virtually unchanged over the past 50 years. This is especially true in the genetic counseling profession where 90% of genetic counselors in the most recent Professional Status Survey reported as White. In order to improve access to genetic services and education for minority families, it is important to increase the availability of minority genetic healthcare providers. The Health Resources and Services Administration funded Western States Regional Genetics Network has created a Minority Genetic Professionals Network (MGPN) to recruit and mentor high school and undergraduate students to enter genetic professions such as genetic counseling. The MGPN has also expanded to provide support, education, and mentor matching for current practicing genetic counselors and genetic counseling students. This Network is an initial step towards developing a more diverse genetics workforce to meet the needs of diverse families in the United States.
Assuntos
Aconselhamento Genético , Grupos Minoritários/estatística & dados numéricos , Recursos Humanos , Diversidade Cultural , Pessoal de Saúde , Humanos , Mentores , Estados UnidosRESUMO
Zika virus infection during pregnancy can cause congenital brain and eye abnormalities and is associated with neurodevelopmental abnormalities (1-3). In areas of the United States that experienced local Zika virus transmission, the prevalence of birth defects potentially related to Zika virus infection during pregnancy increased in the second half of 2016 compared with the first half (4). To update the previous report, CDC analyzed population-based surveillance data from 22 states and territories to estimate the prevalence of birth defects potentially related to Zika virus infection, regardless of laboratory evidence of or exposure to Zika virus, among pregnancies completed during January 1, 2016-June 30, 2017. Jurisdictions were categorized as those 1) with widespread local transmission of Zika virus; 2) with limited local transmission of Zika virus; and 3) without local transmission of Zika virus. Among 2,004,630 live births, 3,359 infants and fetuses with birth defects potentially related to Zika virus infection during pregnancy were identified (1.7 per 1,000 live births, 95% confidence interval [CI] = 1.6-1.7). In areas with widespread local Zika virus transmission, the prevalence of birth defects potentially related to Zika virus infection during pregnancy was significantly higher during the quarters comprising July 2016-March 2017 (July-September 2016 = 3.0; October-December 2016 = 4.0; and January-March 2017 = 5.6 per 1,000 live births) compared with the reference period (January-March 2016) (1.3 per 1,000). These findings suggest a fourfold increase (prevalence ratio [PR] = 4.1, 95% CI = 2.1-8.4) in birth defects potentially related to Zika virus in widespread local transmission areas during January-March 2017 compared with that during January-March 2016, with the highest prevalence (7.0 per 1,000 live births) in February 2017. Population-based birth defects surveillance is critical for identifying infants and fetuses with birth defects potentially related to Zika virus regardless of whether Zika virus testing was conducted, especially given the high prevalence of asymptomatic disease. These data can be used to inform follow-up care and services as well as strengthen surveillance.
Assuntos
Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/virologia , Vigilância da População , Complicações Infecciosas na Gravidez/virologia , Infecção por Zika virus/complicações , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Gravidez , Prevalência , Porto Rico/epidemiologia , Estados Unidos/epidemiologia , Ilhas Virgens Americanas/epidemiologiaRESUMO
PURPOSE: The Institute of Medicine recommended the utilization of metrics to improve quality in health care, although they have rarely been used in genetics. This study developed and tested a set of metrics for a quality assessment tool for genetic services METHODS: A systematic review of literature, guidelines, and consensus statements identified candidate measures for a possible assessment tool. An expert panel conducted a modified Delphi technique to rank the metrics. Ratings were computed to generate a score for each metric, creating a set of metrics for consensus discussions, pilot testing, and feasibility testing in eight Midwestern states. RESULTS: The panel reduced 61 candidate metrics to 21 for pilot testing in two states, which further limited and refined the set to 16 metrics. These 16 were categorized into five domains: service capacity, access to care, data systems, performance reporting, and workforce. Further feasibility testing in one Regional Genetics Collaborative identified the tool's usefulness and barriers to implementation. CONCLUSIONS: These quality metrics for both clinical and public health genetics across the lifespan may help medical professionals and policymakers evaluate quality and cost-effectiveness of genetic services on a statewide basis and stimulate outcome-oriented, health services research in medical genetics and genomics.
Assuntos
Atenção à Saúde/normas , Serviços em Genética/normas , Melhoria de Qualidade/normas , Técnica Delphi , Guias como Assunto , Humanos , Estados Unidos/epidemiologiaRESUMO
Zika virus infection during pregnancy can cause serious birth defects, including microcephaly and brain abnormalities (1). Population-based birth defects surveillance systems are critical to monitor all infants and fetuses with birth defects potentially related to Zika virus infection, regardless of known exposure or laboratory evidence of Zika virus infection during pregnancy. CDC analyzed data from 15 U.S. jurisdictions conducting population-based surveillance for birth defects potentially related to Zika virus infection.* Jurisdictions were stratified into the following three groups: those with 1) documented local transmission of Zika virus during 2016; 2) one or more cases of confirmed, symptomatic, travel-associated Zika virus disease reported to CDC per 100,000 residents; and 3) less than one case of confirmed, symptomatic, travel-associated Zika virus disease reported to CDC per 100,000 residents. A total of 2,962 infants and fetuses (3.0 per 1,000 live births; 95% confidence interval [CI] = 2.9-3.2) (2) met the case definition. In areas with local transmission there was a non-statistically significant increase in total birth defects potentially related to Zika virus infection from 2.8 cases per 1,000 live births in the first half of 2016 to 3.0 cases in the second half (p = 0.10). However, when neural tube defects and other early brain malformations (NTDs)§ were excluded, the prevalence of birth defects strongly linked to congenital Zika virus infection increased significantly, from 2.0 cases per 1,000 live births in the first half of 2016 to 2.4 cases in the second half, an increase of 29 more cases than expected (p = 0.009). These findings underscore the importance of surveillance for birth defects potentially related to Zika virus infection and the need for continued monitoring in areas at risk for Zika.
Assuntos
Anormalidades Congênitas/epidemiologia , Anormalidades Congênitas/virologia , Vigilância da População , Infecção por Zika virus/complicações , Feminino , Humanos , Lactente , Recém-Nascido , Gravidez , Complicações Infecciosas na Gravidez/virologia , Prevalência , Porto Rico/epidemiologia , Estados Unidos/epidemiologiaRESUMO
The Western States Genetic Services Collaborative (WSGSC) recognized the need for clear and understandable information about the Affordable Care Act (ACA) for families throughout the life course. The genetic counselors working in the WSGSC developed, tested, and implemented a web resource ( http://www.westernstatesgenetics.org/ACA_home.htm ) to help families navigate information about the ACA tailored to their life situation. The training and experience of genetic counselors provide the skills needed to translate complicated information, like that of the ACA, into formats that the general public can comprehend. The website went public in October 2013, and it has been positively received. The development of this website is a good case study in how genetic counseling skills can be applied to public health education and improving health literacy.
Assuntos
Aconselhamento Genético , Educação em Saúde/organização & administração , Patient Protection and Affordable Care Act/organização & administração , Humanos , Internet , Estados Unidos , Recursos HumanosRESUMO
Promoter hypermethylation of tumor suppressor genes (TSGs) is a common feature of primary cancer cells. However, to date the somatic epigenetic events that occur in head and neck squamous cell carcinoma (HNSCC) tumorigenesis have not been well-defined. In the present study, we analyzed the promoter methylation status of the genes mutL homolog 1 (MLH1), Ras-association domain family member 1 (RASSF1A) and O-6-methylguanine-DNA methyltransferase (MGMT) in 23 HNSCC samples, three control tissues and one HNSCC cell line (UM-SCC 33) using methylation-specific PCR (MSP). The expression of the three proteins was quantified by semi-quantitative immunohistochemical analysis. The cell line was treated with the demethylating agent 5-azacytidine (5-Aza) and the methylation status after 5-Aza treatment was analyzed by MSP and DNA sequencing. Proliferation was determined by Alamar blue staining. We found that the MGMT promoter in 57% of the analyzed primary tumor samples and in the cell line was hypermethylated. The MLH promoter was found to be methylated in one out of 23 (4%) tumor samples while in the examined cell line the MLH promoter was unmethylated. The RASSF1A promoter showed methylation in 13% of the tumor samples and in the cell line. MGMT expression in the group of tumor samples with a hypermethylated promoter was statistically significantly lower compared to the group of tumors with no measured hypermethylation of the MGMT promoter. After treatment of the cell line with the demethylating agent 5-Aza no demethylation of the methylated MGMT and RASSF1A genes were determined by MSP. DNA sequencing verified the MSP results, however, increased numbers of unmethylated CpG islands in the promoter region of MGMT and RASSF1A were observed. Proliferation was significantly (p<0.05) reduced after treatment with 5-Aza. In summary, we have shown promoter hypermethylation of the tumor suppressor genes MGMT and RASSF1A in HNSCC, suggesting that this epigenetic inactivation of TSGs may play a role in the development of HNSCC. 5-Aza application resulted in partial demethylation of the MGMT and RASSF1A TSGs and reduced proliferation of the tumor cells suggesting further evaluation of 5-Aza for HNSCC treatment.
Assuntos
Proteínas Adaptadoras de Transdução de Sinal/genética , Azacitidina/farmacologia , Carcinoma de Células Escamosas/genética , Proliferação de Células/efeitos dos fármacos , Metilação de DNA/efeitos dos fármacos , Metilases de Modificação do DNA/genética , Enzimas Reparadoras do DNA/genética , Inibidores Enzimáticos/farmacologia , Genes Supressores de Tumor , Neoplasias de Cabeça e Pescoço/genética , Proteínas Nucleares/genética , Regiões Promotoras Genéticas/efeitos dos fármacos , Proteínas Supressoras de Tumor/genética , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Idoso , Idoso de 80 Anos ou mais , Sequência de Bases , Carcinoma de Células Escamosas/metabolismo , Carcinoma de Células Escamosas/patologia , Estudos de Casos e Controles , Linhagem Celular Tumoral , Ilhas de CpG , Metilases de Modificação do DNA/antagonistas & inibidores , Metilases de Modificação do DNA/metabolismo , Enzimas Reparadoras do DNA/antagonistas & inibidores , Enzimas Reparadoras do DNA/metabolismo , Remoção de Radical Alquila , Relação Dose-Resposta a Droga , Regulação para Baixo , Feminino , Neoplasias de Cabeça e Pescoço/metabolismo , Neoplasias de Cabeça e Pescoço/patologia , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Dados de Sequência Molecular , Proteína 1 Homóloga a MutL , Proteínas Nucleares/metabolismo , Reação em Cadeia da Polimerase , Análise de Sequência de DNA , Proteínas Supressoras de Tumor/antagonistas & inibidores , Proteínas Supressoras de Tumor/metabolismoRESUMO
Aberrant inactivation of tumor suppressor genes by promoter hypermethylation has been recognized as a crucial step of tumor development and is related to aggressiveness and therapy resistance. To identify potential novel treatment strategies, we evaluated pharmacological genome demethylation for the increase of irradiation treatment effectiveness in head and neck squamous cell carcinoma (HNSCC) in this in vitro study. HNSCC cells were cultured with 2 different concentrations of 5-azacytidine (5-Aza) for 72 h, followed by a single fraction irradiation with 4 or 50 Gy, respectively. To show successful genome demethylation, the methylation status of the tumor suppressor gene hic1 (hypermethylated in cancer) promoter was analyzed by methylation specific PCR (MSP) as well as hic1 transcription by quantitative RT-PCR. Survival, apoptosis, viability, and migration of the tumor cells were analyzed as functional parameters of combined treatment response. After 5-Aza treatment the hic1 promoter was demethylated and gene transcription restored demonstrating genome demethylation. 5-Aza treated cells tended to be less viable and showed decreased survival indicated by lower colony numbers. Apoptosis and migration were not affected. The combined application of irradiation and 5-Aza significantly reduced survival compared to the single treatments. Accordingly, apoptosis was strongly increased after combined 4 Gy/5-Aza treatment. Viability was not additionally affected by combined treatment. Migration was affected weakly by combined high dosage irradiation/5Aza treatment. Our data show that the combined application of 5-Aza and irradiation is effective in vitro. A demethylating concept prior to irradiation should be further evaluated for its potential to reduce irradiation resistance.
Assuntos
Antimetabólitos Antineoplásicos/farmacologia , Azacitidina/farmacologia , Carcinoma de Células Escamosas/genética , Metilação de DNA/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/genética , Tolerância a Radiação/efeitos dos fármacos , Linhagem Celular Tumoral , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Humanos , Regiões Promotoras Genéticas/efeitos dos fármacos , Carcinoma de Células Escamosas de Cabeça e Pescoço , Ativação Transcricional/efeitos dos fármacosRESUMO
Promoter hypermethylation of tumor suppressor genes is a common feature of primary cancer cells. However, at date the somatic epigenetic events that occur in head and neck squamous cell carcinoma (HNSCC) tumorigenesis are not yet been well defined. In the present study we analysed the methylation status of the gene hypermethylated in cancer-1 (hic1), a gene located on chromosome 17p13.3, a region frequently lost in HNSCC. We analysed 22 HNSCC samples and three cell lines using methylation specific PCR (MSP). We found hic1 methylated in 21 out of 22 samples and in all three cell lines. Treatment of the cell lines with the demethylating agent 5-Azacytidin (5-Aza) resulted in the demethylation of the hic1 promoter and reactivation of hic1 expression as determined by MSP, qPCR and Western blot. Functional analyses revealed decreased proliferative activity and colony forming ability of treated cells. In summary, we found in HNSCC hic1 regulated by promoter methylation. 5-Aza application resulted in the reexpression of hic1 and was followed by decreased aggressiveness of the cancer cells. Our data indicate that hic1 might be a player in HNSCC development and suggest further evaluation of 5-Aza for HNSCC treatment.
Assuntos
Carcinoma de Células Escamosas/patologia , Metilação de DNA/efeitos dos fármacos , Neoplasias de Cabeça e Pescoço/patologia , Fatores de Transcrição Kruppel-Like/metabolismo , Adulto , Idoso , Antimetabólitos Antineoplásicos/uso terapêutico , Azacitidina/uso terapêutico , Carcinoma de Células Escamosas/tratamento farmacológico , Carcinoma de Células Escamosas/genética , Carcinoma de Células Escamosas/metabolismo , Linhagem Celular Tumoral , Metilação de DNA/fisiologia , Feminino , Regulação Neoplásica da Expressão Gênica/genética , Genes Supressores de Tumor , Neoplasias de Cabeça e Pescoço/tratamento farmacológico , Neoplasias de Cabeça e Pescoço/genética , Neoplasias de Cabeça e Pescoço/metabolismo , Humanos , Masculino , Pessoa de Meia-Idade , Invasividade Neoplásica , Regiões Promotoras GenéticasRESUMO
Hepatitis B virus (HBV) budding from infected cells is a tightly regulated process that requires both core and envelope structures. Here we report that HBV uses cellular gamma2-adaptin and Nedd4, possibly in conjunction with ubiquitin, to coordinate its assembly and release. In search of interaction partners of the viral L envelope protein, we previously discovered gamma2-adaptin, a putative endosomal sorting and trafficking adaptor of the adaptor protein complex family. We now demonstrate that the viral core interacts with the same gamma2-adaptor and that disruption of the HBV/gamma2-adaptin interactions inhibits virus production. Mutational analyses revealed a hitherto unknown ubiquitin-binding activity of gamma2-adaptin, specified by a ubiquitin-interacting motif, which contributes to its interaction with core. For core, the lysine residue at position 96, a potential target for ubiquitination, was identified to be essential for both gamma2-adaptin-recognition and virus production. The participation of the cellular ubiquitin system in HBV assembly was further suggested by our finding that core interacts with the endosomal ubiquitin ligase Nedd4, partly via its late domain-like PPAY sequence. Overexpression of a catalytically inactive Nedd4 mutant diminished HBV egress, indicating that protein ubiquitination is functionally involved in virus production. Additional evidence for a link of HBV assembly to the endosomal machinery was provided by immunolabeling studies that demonstrated colocalization of core and L with gamma2-adaptin in compartments positive for the late endosomal marker CD63. Together, these data indicate that an enveloped DNA virus exploits a new ubiquitin receptor together with endosomal pathway functions for egress from hepatocytes.
Assuntos
Subunidades gama do Complexo de Proteínas Adaptadoras/química , Vírus da Hepatite B/metabolismo , Ubiquitina-Proteína Ligases/química , Ubiquitina/química , Subunidades gama do Complexo de Proteínas Adaptadoras/metabolismo , Sequência de Aminoácidos , Antígenos CD/biossíntese , Catálise , DNA/química , Complexos Endossomais de Distribuição Requeridos para Transporte , Humanos , Lisina/química , Dados de Sequência Molecular , Ubiquitina-Proteína Ligases Nedd4 , Glicoproteínas da Membrana de Plaquetas/biossíntese , Conformação Proteica , Homologia de Sequência de Aminoácidos , Tetraspanina 30 , TransfecçãoRESUMO
For functional diversity, the large (L) envelope protein of hepatitis B virus (HBV) acquires a dual transmembrane topology via co-translational membrane integration of the S region and partial post-translational translocation of the preS subdomain. Because each process requires the second transmembrane segment (TM2), we explored the action of this determinant by using protease protection analysis of mutant L proteins. We demonstrated that neither the disruption of a leucine zipper-like motif by multiple alanine substitutions nor the flanking charges of TM2 affected the topological reorientation of L. The dispensability of both putative subunit interaction modules argues against a link between preS post-translocation and envelope assembly. Phenotypic mixing experiments revealed that the preS and S protein domains of the related duck HBV L polypeptide failed to substitute functionally for the topogenic elements of HBV in directing the correct L topogenesis, implicating different translocation mechanisms used by the two hepadnavirus genera.
Assuntos
Vírus da Hepatite B/fisiologia , Processamento de Proteína Pós-Traducional , Proteínas do Envelope Viral/metabolismo , Motivos de Aminoácidos , Sequência de Aminoácidos , Substituição de Aminoácidos , Transporte Biológico , Retículo Endoplasmático/virologia , Dados de Sequência Molecular , Proteínas do Envelope Viral/genética , Montagem de VírusRESUMO
OBJECTIVE: A DNA disc chip assay, based on comparative genomic hybridization, was designed to measure changes in sperm DNA intensities. The objective was to analyze the DNA integrity of hyperactive sperm cells after mild heat treatment. DESIGN: The assay based on a multiple cell comet assay was used to analyze changes in genomic DNA. Washed sperm DNA were tested on the assay and images stored in a microarray design. SETTING: Clinical and academic research environment. PATIENT(S): Frozen-thawed washed sperm from different donors (n = 7). INTERVENTION(S): Discarded sperm leftover from trial washes carried out at 37 degrees and 40 degrees C were frozen and processed for the DNA disc chip assay. MAIN OUTCOME MEASURE(S): Fluorescent intensities of DNA disc chips and sperm variables. RESULT(S): Heat treatment resulted in more than eightfold increase in sperm hyperactive motility with little degradation in DNA integrity. Sperm with low hyperactivation was associated with alterations in DNA after heat treatment. CONCLUSION(S): The DNA disc chip assay was simple, inexpensive, and permitted assisted reproduction technologies laboratories to use comparative genomic hybridization for cytogenotoxicity testing. However, the assay required manual processing, a fluorescent microscope, and computer. The data showed an association between sperm hyperactivation and DNA integrity suggesting that the hyperactivation marker may be used for selecting quality sperm for intracytoplasmic sperm injection. More studies are needed to examine temperature effects on ejaculated human sperm.
Assuntos
DNA/fisiologia , Hibridização de Ácido Nucleico , Análise de Sequência com Séries de Oligonucleotídeos , Espermatozoides/metabolismo , Relação Dose-Resposta a Droga , Temperatura Alta , Humanos , Peróxido de Hidrogênio/administração & dosagem , Peróxido de Hidrogênio/farmacologia , Masculino , Oxidantes/farmacologia , Motilidade dos Espermatozoides/efeitos dos fármacos , Espermatozoides/efeitos dos fármacosRESUMO
PURPOSE: A DNA disc chip assay based on comparative genomic hybridization (CGH) was developed to measure sperm DNA integrity. The objective was to correlate DNA integrity of heat-treated sperm with the sperm capacitation index (CI) determined from the sperm penetration assay. METHODS: Basic semen and kinematic parameters were measured (N = 6). Sperm were washed in two-layer colloid suspensions and split portions incubated at either 3 degrees C (control) or 40 degrees C for 4 h. Single-stranded DNA of heated sperm were stained in SYBR Gold and hybridized to bisbenzimide (Hoechst 33342) stained control DNA in a membrane disc. Fluorescent intensities of the discs were measured and correlation analyses with sperm parameters performed. RESULTS: Sperm CI was positively correlated (R = 0.737) with sperm DNA integrity. Two populations of sperm could be discerned: low capacitating sperm that initiated apoptosis and high capacitating sperm unaffected by heat shock treatment. The remaining parameters were not related to sperm DNA stability. CONCLUSIONS: Fragile DNA were found in a population of sperm associated with poor capacitation characteristics and apoptosis was observed after heat treatment. The results suggested that sperm dysfunction might be due to apoptotic sperm DNA resulting from an elevated temperature in the surroundings. The data suggested that the second population of high capacitating sperm induced chaperones such as heat shock proteins hsp 70 to protect against apoptosis.