Does FTO have a paradoxical effect in fetal life?

Area of Science:

• Genetics and Epigenetics
• Human Physiology
• Public Health

Background:

• Low birth weight is a known risk factor for developing obesity later in life.
• The fat mass and obesity-associated (FTO) gene has been recently identified as a key genetic factor influencing adult obesity.
• A hypothesis suggests that genetic variants predisposing to obesity may also reduce fetal weight.

Purpose of the Study:

• To investigate the association between specific FTO gene polymorphisms and birth weight.
• To test the hypothesis that obesity-risk genetic variants also influence fetal growth.

Main Methods:

• Analysis of a singleton, full-term birth cohort comprising 494 newborn-mother pairs.
• Genotyping of FTO gene variants rs9939609 and rs9930506.
• Statistical analysis to determine the association between FTO risk alleles and birth weight, with adjustments for confounding factors.

Main Results:

• Obesity risk alleles for FTO variants rs9939609 and rs9930506 were significantly associated with lower birth weight.
• Each risk allele was associated with a mean birth weight reduction of approximately 79-84 grams.
• These associations remained significant after adjusting for maternal factors and other variables influencing birth weight.

Conclusions:

• FTO gene variants associated with adult obesity predisposition are also linked to reduced birth weight.
• This supports the hypothesis of a common genetic basis for both low birth weight and adult obesity.
• The findings highlight the role of FTO gene in early developmental programming related to weight.