Related Experiment Videos
A cytogenetic survey of 14,835 consecutive liveborns
1Kitasato University School of Nursing, Kanagawa, Japan.
Insights
Major chromosome abnormalities were found in 6.27 per 1,000 liveborn infants. This study details sex chromosome and autosomal abnormalities, including trisomies and translocations, in a large newborn cohort.
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.
Abstract:
The results of chromosome studies on cultured umbilical cord blood lymphocytes from a consecutive series of 14,835 liveborn infants (7,608 males and 7,227 females) are described. Ninety-three infants (6.27 per 1,000) had a major chromosome abnormality. Of these, thirty-one infants (2.09 per 1,000) had sex chromosome abnormalities. Seven male infants had a 47,XXY karyotype, five had a 47,XYY karyotype, and three were mosaics. One male had a ring Y chromosome in all cells examined. A pericentric inversion of the Y chromosome was found in one case. Seven female infants had a 47,XXX karyotype, one had a 45,X karyotype and six were mosaics. Sixty-two infants (4.18 per 1,000) had autosomal abnormalities. There were twenty-one infants with trisomy 21 including one mosaic, six infants with trisomy 18, and two infants with trisomy 13 of a Robertsonian translocation type. Three infants had an unbalanced derivative chromosome resulting from a parental reciprocal translocation. Two infants with a partial monosomy of chromosome 13 were detected. There were four infants carrying an additional small marker chromosome. Twenty-four infants (1.62 per 1,000) had a balanced structural rearrangement of the autosomes; eleven with a Robertsonian translocation, eleven with a reciprocal translocation, and two with a pericentric inversion. The incidence of each type of major chromosome abnormality in this study was quite similar to that obtained from previous newborn surveys.