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Cytogenomic description of a Mexican cohort with differences in sex development
Grecia C Olivera-Bernal1, Marlon De Ita-Ley1,2, Edgar F Ricárdez-Marcial3
1Medical Research Unit in Human Genetics, Instituto Mexicano del Seguro Social (IMSS)/Hospital de Pediatría, Centro Médico Nacional SXXI, Ave. Cuauhtémoc 330, 06720, Mexico City, Mexico.
Background:
Differences in Sex Development (DSD) is a heterogeneous group of congenital alterations that affect inner and/or outer primary sex characters. Although these conditions do not represent a mortality risk, they can have a severe psycho-emotional impact if not appropriately managed. The genetic changes that can give rise to DSD are diverse, from chromosomal alterations to single base variants involved in the sexual development network. Epidemiological studies about DSD indicate a global frequency of 1:4500-5500, which can increase to 1:200-300, including isolated anatomical defects. To our knowledge, this study is the first to describe epidemiological and genetic features of DSD in a cohort of Mexican patients of a third-level care hospital.
Methods:
Descriptive and retrospective cross-sectional study that analyzed DSD patients from 2015 to 2021 attended a Paediatric Hospital from Mexico City.
Results:
One hundred one patients diagnosed with DSD were registered and grouped into different entities according to the Chicago consensus statement and the diagnosis defined by the multidisciplinary group. Of the total, 54% of them belong to the chromosomal DSD classification, 16% belongs to 46, XX and 30% of them belongs to the 46, XY classification.
Conclusion:
The frequency for chromosomal DSDs was consistent with the literature; however, we found that DSD 46, XY is more frequent in our cohort, which may be due to the age of the patients captured, the characteristics of our study population, or other causes that depend on the sample size.
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