A cytogenetic survey of 14,835 consecutive liveborns

Area of Science:

• Human Genetics
• Clinical Cytogenetics
• Neonatal Medicine

Background:

• Chromosome abnormalities are a significant cause of birth defects and developmental disorders.
• Newborn screening for chromosomal abnormalities is crucial for early diagnosis and intervention.
• Previous newborn surveys have established baseline incidence rates for various chromosomal conditions.

Purpose of the Study:

• To report the incidence and types of major chromosome abnormalities in a large, consecutive series of liveborn infants.
• To compare findings with previous newborn cytogenetic surveys.
• To provide updated epidemiological data on chromosomal abnormalities in newborns.

Main Methods:

• Chromosome analysis of cultured umbilical cord blood lymphocytes.
• Consecutive series of 14,835 liveborn infants.
• Karyotyping to identify numerical and structural chromosomal abnormalities.

Main Results:

• A total of 93 infants (6.27 per 1,000) had major chromosome abnormalities.
• Sex chromosome abnormalities were observed in 2.09 per 1,000 infants (e.g., 47,XXY, 47,XXX, 45,X).
• Autosomal abnormalities occurred in 4.18 per 1,000 infants (e.g., trisomy 21, trisomy 18, trisomy 13, translocations).
• Balanced structural rearrangements were found in 1.62 per 1,000 infants.

Conclusions:

• The incidence of major chromosome abnormalities in this cohort is consistent with previous newborn surveys.
• Detailed characterization of chromosomal abnormalities aids in understanding their impact on infant health.
• Continued cytogenetic surveillance of newborns is important for public health monitoring.