Abstract
Background: Genetic stability of the chromosome is preserved by telomeres, which act as biological markers of ageing. The Relative Telomere Length (RTL) of a fetus has been found highly variable at birth under the influence of multiple risk factors.
Objective: The purpose of this study was to find an association between maternal factors like obesity and low hemoglobin with cord blood RTL.
Methods: This study used a Quantitative Real-time Polymerase chain reaction (qPCR) to measure RTL in blood samples of 250 mother-newborn dyads. Participants having the age of 18-35 years and gestational age 37 weeks or above were divided into three BMI groups, normal (18.5-24.5 kg/m2), overweight (25-29.9 kg/m2), and obese (>30kg/m2). Association among maternal parameters and cord RTL was analyzed by spearmen correlation, Kruskal Wallis, and Man Whitney U test.
Results: Overall newborn cord blood RTL in base pair (bp) (mean ± SD) was longer (6915±1425, 6469+1077,6485±1015) compared to mother blood (bp) (6471±1144, 6322+838, 6401 ±993) (p<0.05) in all three groups of BMI, whereas shortest cord RTL (6485bp±1015) was observed in the newborns of obese females (p<0.597). A positive correlation (R=0.806) was between the low hemoglobin and cord blood RTL (p=<0.05); however, a significant decrease in cord RTL (7685bp±321) was observed with an increase in BMI (p<0.05). In the newborn gender, boys showed longer RTL (7509bp ±830) and had mothers with overweight, 82(55%), whereas the majority of girls, 20(57%), were born to females with normal BMI (p=0.06).
Conclusion: Low hemoglobin was found a significant risk factor for the modification of telomeres in the newborns of Pakistani females. In females having overweight and obesity, shorter cord RTL was observed.
Keywords: Telomeres, telomerase, fetal programming, Body Mass Index (BMI), hemoglobin (Hb), newborn.
Graphical Abstract
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