The prevalence and patterns of chromosome abnormalities in newborns with major congenital anomalies: A retrospective study from Saudi Arabia

Abstract

congenital anomalies, chromosome abnormalities, birth prevalence, newborns, Down syndrome Congenital anomalies are a worldwide health problem that places a burden on the family and society. Chromosome abnormalities are one of the leading causes for congenital anomalies in newborns. Despite the remarkable development in cytogenetic services in the past years, still there are limited data from Middle East countries. The current study aimed to evaluate the prevalence and patterns of chromosomal aberrations in newborns admitted to the neonatal intensive care unit (NICU) with major congenital anomalies at Medina province in the western region of Saudi Arabia. Out of 2,541 live births, 150 newborns were selected based on the presence of major birth defects. Demographic and clinical data were collected from hospital medical records and statistically analyzed. The prevalence of major congenital anomalies was 10.7/1,000 live births (95% CI: 9.076-12.583). The most common congenital anomalies in descending order were congenital heart disease, musculoskeletal and chromosome abnormalities. The birth prevalence of chromosome abnormalities was 4.22/1,000 live births (95% CI: 3.211-5.441). The most common chromosome abnormality was Down syndrome-nondisjunction type (66%). Advanced parental age was strongly associated with chromosome aberrations (p < 0.001) while consanguinity was evident in cases with normal karyotype (p < 0.001). High birth prevalence of chromosome abnormalities in newborns with congenital anomalies in Al Madinah was evident and advanced parental age is a potential risk factor. A local registry system for congenital anomalies is highly recommended to provide proper health services to high risk families.

Proportion of Chromosomal Disorders and Their Patterns among Births with Congenital Anomalies in Africa: A Systematic Review and Meta-Analyses

“…In the current systematic review and meta-analyses, Down syndrome (trisomy 21) was the most common chromosomal disorder reported; the pooled proportion among births with congenital anomalies was 7.6% (95% CI: 5.70, 9.67). Te result was supported by the studies conducted in the USA, which reported that Down syndrome is the most commonly identifed genetic form of mental retardation and the leading cause of specifc birth defects and medical conditions [105], and it was in line with the studies conducted in the Arab world [1,106,107] and Europe [108].…”

“…Chromosomal anomalies are the leading causes of congenital anomalies, whether inherited or newly discovered [ 1 , 2 ]. Worldwide, among the diverse causes of congenital anomalies, genetic/chromosomal disorders are still on a disturbing rise, which leads to a major health problem; indeed, critical control of environmental diseases has been realized [ 3 ].…”

Detection rates of abnormalities in over 10,000 amniotic fluid samples at a single laboratory

“…The detection results of common aneuploidies were exactly the same between SNP array and karyotyping, including autosomal trisomy (21,18,13,9), sex chromosomal monosomy and sex chromosomal trisomy. In the 66 cases of mosaicism that were detected by karyotyping, 55 (83.3%) were identified by SNP array (Table 5).…”

“…It was reported that in China the prevalence of birth defects is about 5.6%, with chromosomal abnormalities accounting for an important proportion [ 20 ]. Prior studies have implied that trisomy 21 is the most common chromosomal abnormality of birth defects, followed by sex chromosomal abnormalities and trisomy 18 [ 21 – 23 ]. In our study, trisomy 21 was also the most common abnormality, followed by mosaicism, and trisomy 18 in numerical chromosomal abnormalities in the second trimester.…”

“…Such techniques commonly used in our centre include BACs-on-Beads (BoBs) assay, single nucleotide polymorphism (SNP) array and fluorescence in situ hybridization (FISH). The BoBs assay is mainly used for the rapid detection of 5 common chromosome aneuploidies (21,18,13, X and Y) and 9 particular microdeletion syndromes [10]. The SNP array method is microarraybased to study the copy number of chromosome and extraordinarily improves the detection of CNVs in the genome [11].…”