Genetics and genomic medicine in Ecuador

Genetic knowledge and attitudes towards genetic testing among final-year medical students at a public university in Ecuador

Background

Genetics plays a crucial role in the field of medicine, offering numerous applications. However, health professionals often have insufficient knowledge in this area. Therefore, it is essential to provide appropriate genetics education during university studies.

Aim

This study aimed to assess the knowledge and attitudes towards genetic testing among final-year medical students at a public university in Ecuador.

Methods

A cross-sectional study was conducted involving final-year medical students from a public university in Ecuador. The third version of the Genetic Literacy and Attitudes Survey was administered between April and May 2022. The study examined sociodemographic characteristics, genetic knowledge, and attitudes towards genetic testing.

Results

The study included 153 medical students, of which 58.2% identified as female. Most participants fell within the age range of 22 to 25 years old (85.0%). Regarding genetic knowledge, three-quarters of the participants (75.2%) demonstrated intermediate proficiency, while only 9.80% possessed a high level of knowledge. Attitudes towards the clinical and therapeutic applications of genetics, scientific advancements, access to conventional medicine, and other related topics were found to be appropriate.

Conclusion

The findings suggest that most final-year medical students at a public university in Ecuador have intermediate genetic knowledge and hold appropriate attitudes towards genetic testing. However, higher education institutions should conduct a comprehensive analysis and restructure their curricula to better prepare students for the medical and technological challenges of the 21st century.

Clinical, genetic and microbiological characterization of pediatric patients with cystic fibrosis in a public Hospital in Ecuador

BACKGROUND

To carry out a complete clinical, pathological, genetic and microbiological characterization of pediatric patients with molecular confirmed cystic fibrosis (CF) attending the Carlos Andrade Marín Hospital (HCAM) within the study period.

METHODS

A cross-sectional analysis of the pediatric population with a confirmed diagnosis of CF disease who attended HCAM, one of the largest tertiary-level hospitals in Ecuador, between 2017 and 2018 was performed. All demographic, clinical and genetic variables were obtained from the electronic medical records (EMR) stored by the hospital.

RESULTS

Forty seven patients with CF were included in the study. Gender distribution was similar between male (48.9%, n = 23) and female patients (51.1%, n = 24). The Tiffeneau-Pinelli index (FEV₁/FVC) changed significantly after nine months post-diagnosis (85.55 ± 13.26; p < 0.05). The most common pathogenic genetic variants were F508del, found in 52.78% of the cohort (n = 19); H609R, found in 36.11% (n = 13); g.204099A > C, found in 14.1% (n = 7), followed by G85E and the N1303K with 11.11% (n = 3) each.

CONCLUSIONS

To our best knowledge, this is the first study exploring the clinical, genetic and bacteriological profile of CF's patients in Ecuador. Within the cohort of patients, an important and unique genetic feature was characterized by the presence of the g.204099A > C and the c.206359C > A homozygous polymorphism as well as the presence of the H609R variant, a mutation only reported among Ecuadorians.

Multi-institutional experience of genetic diagnosis in Ecuador: National registry of chromosome alterations and polymorphisms

BACKGROUND

Detection of chromosomal abnormalities is crucial in various medical areas; to diagnose birth defects, genetic disorders, and infertility, among other complex phenotypes, in individuals across a wide range of ages. Hence, the present study wants to contribute to the knowledge of type and frequency of chromosomal alterations and polymorphisms in Ecuador.

METHODS

Cytogenetic registers from different Ecuadorian provinces have been merged and analyzed to construct an open-access national registry of chromosome alterations and polymorphisms.

RESULTS

Of 28,806 karyotypes analyzed, 6,008 (20.9%) exhibited alterations. Down syndrome was the most frequent autosome alteration (88.28%), followed by Turner syndrome (60.50%), a gonosome aneuploidy. A recurrent high percentage of Down syndrome mosaicism (7.45%) reported here, as well as by previous Ecuadorian preliminary registries, could be associated with geographic location and admixed ancestral composition. Translocations (2.46%) and polymorphisms (7.84%) were not as numerous as autosomopathies (64.33%) and gonosomopathies (25.37%). Complementary to conventional cytogenetics tests, molecular tools have allowed identification of submicroscopic alterations regions or candidate genes which can be possibly implicated in patients' symptoms and phenotypes.

CONCLUSION

The Ecuadorian National Registry of Chromosome Alterations and Polymorphisms provides a baseline to better understand chromosomal abnormalities in Ecuador and therefore their clinical management and awareness. This data will guide public policy makers to promote and financially support cytogenetic and genetic testing.

Analysis of Racial/Ethnic Representation in Select Basic and Applied Cancer Research Studies

Over the past decades, consistent studies have shown that race/ethnicity have a great impact on cancer incidence, survival, drug response, molecular pathways and epigenetics. Despite the influence of race/ethnicity in cancer outcomes and its impact in health care quality, a comprehensive understanding of racial/ethnic inclusion in oncological research has never been addressed. We therefore explored the racial/ethnic composition of samples/individuals included in fundamental (patient-derived oncological models, biobanks and genomics) and applied cancer research studies (clinical trials). Regarding patient-derived oncological models (n = 794), 48.3% have no records on their donor's race/ethnicity, the rest were isolated from White (37.5%), Asian (10%), African American (3.8%) and Hispanic (0.4%) donors. Biobanks (n = 8,293) hold specimens from unknown (24.56%), White (59.03%), African American (11.05%), Asian (4.12%) and other individuals (1.24%). Genomic projects (n = 6,765,447) include samples from unknown (0.6%), White (91.1%), Asian (5.6%), African American (1.7%), Hispanic (0.5%) and other populations (0.5%). Concerning clinical trials (n = 89,212), no racial/ethnic registries were found in 66.95% of participants, and records were mainly obtained from Whites (25.94%), Asians (4.97%), African Americans (1.08%), Hispanics (0.16%) and other minorities (0.9%). Thus, two tendencies were observed across oncological studies: lack of racial/ethnic information and overrepresentation of Caucasian/White samples/individuals. These results clearly indicate a need to diversify oncological studies to other populations along with novel strategies to enhanced race/ethnicity data recording and reporting.

Cancer risk associated with living at high altitude in Ecuadorian population from 2005 to 2014

Background and aims

Cancer is a leading cause of death in Ecuador with high social and economic impact. This study aims to determinate the influence of living at a high altitude on the risk of developing or dying from cancer among the Ecuadorian population.

Methods

This is an ecological and epidemiological analysis of cancer mortality and prevalence rates, based on national data from the Ecuadorian National Statistics and Census Institute, corresponding to the period between 2005 and 2014. This study includes the analysis of various types of cancer: gastric, colorectal, hepatic/bile duct, breast, uterine/cervix, and lymphatic/hematopoietic, using rates of mortality and prevalence. Additionally, the association between the risk of getting or dying from cancer and living at high altitude was investigated. This comparison was made between the population living in Highlands, over 2000 meters above sea level, and low-lying regions.

Results

Living at high altitude was associated with a higher prevalence of cancer and also with a high mortality rate due to cancer. Risk of getting cancer was related to living at a higher altitude, as well as an increased risk of death by cancer: gastric (OR:1.204; p<0.001), colorectal (OR:1.421; p<0.001), hepatic/bile duct (OR:1.184; p<0.001), breast (OR:1.067; p=0.030), or lymphatic/hematopoietic neoplasms (OR:1.135; p<0.001).

Conclusions

Through an epidemiologic analysis, the association between developing or dying from cancer and living at high altitude was obtained. However, further researche is needed to clarify these findings, something that could have a substantial impact on cancer prevention.

The geographic mosaic of Ecuadorian Y-chromosome ancestry

Ecuadorians originated from a complex mixture of Native American indigenous people with Europeans and Africans. We analyzed Y-chromosome STRs (Y-STRs) in a sample of 415 Ecuadorians (145 using the AmpFlSTR^® Yfiler™ system [Life Technologies, USA] and 270 using the PowerPlex^®Y23 system [Promega Corp., USA]; hereafter Yfiler and PPY23, respectively) representing three main ecological continental regions of the country, namely Amazon rainforest, Andes, and Pacific coast. Diversity values are high in the three regions, and the PPY23 exhibits higher discrimination power than the Yfiler set. While summary statistics, AMOVA, and R_ST distances show low to moderate levels of population stratification, inferred ancestry derived from Y-STRs reveal clear patterns of geographic variation. The major ancestry in Ecuadorian males is European (61%), followed by an important Native American component (34%); whereas the African ancestry (5%) is mainly concentrated in the Northwest corner of the country. We conclude that classical procedures for measuring population stratification do not have the desirable sensitivity. Statistical inference of ancestry from Y-STRS is a satisfactory alternative for revealing patterns of spatial variation that would pass unnoticed when using popular statistical summary indices.