Genetic variation in CD38 and breastfeeding experience interact to impact infants' attention to social eye cues

Area of Science:

• Developmental psychology
• Neuroscience
• Genetics

Background:

• Attending to emotional eye cues is a critical human social skill.
• Early development of this skill is influenced by genetic and experiential factors.
• The oxytocin system plays a role in social behavior and is modulated by genetics and early life experiences.

Purpose of the Study:

• To investigate infant attention to emotional eyes in 7-month-olds.
• To examine the influence of CD38 gene variation (rs3796863 polymorphism) and exclusive breastfeeding duration on this attention.
• To explore the interaction between genetic and experiential factors related to the oxytocin system in early social attention.

Main Methods:

• Measuring attention to eye regions of emotional faces in 7-month-old infants.
• Analyzing individual differences based on CD38 rs3796863 genotype.
• Assessing the duration of exclusive breastfeeding as an experiential variable.
• Correlating attention patterns with genetic and breastfeeding data.

Main Results:

• Infants showed a general bias towards fearful eyes.
• Attention to angry and happy eyes varied significantly with exclusive breastfeeding duration and CD38 genotype.
• Extended exclusive breastfeeding enhanced attention to happy eyes and reduced attention to angry eyes, but only in infants with the CC genotype at CD38 rs3796863.
• Infants with CA/AA genotypes showed consistent attention patterns regardless of breastfeeding duration.

Conclusions:

• Early social attention to emotional eyes is modulated by an interaction between endogenous oxytocin availability (via CD38 genotype) and exogenous factors (breastfeeding).
• Breastfeeding duration influences social attention, with effects dependent on specific genetic variations.
• These findings underscore the importance of maternal care and the oxytocin system in shaping infant social-emotional development and responding to eye cues.