Research suggests that the prevalence of children with Major Depressive Disorder in Western cultures ranges from 1.9% to 3.4% among primary school children. Amongst teenagers, up to 9% meet criteria for depression in a given moment and approximately 20% experience depression sometime during adolescence. Studies have also found that among children diagnosed with a depressive episode, there is a 70% rate of recurrence within five years. Furthermore, 50% of children with depression will have a recurrence at least once during their adulthood. While there is no gender difference in depression rates up until age 15, after that age the rate among women doubles compared to men. However, in terms of recurrence rates and symptom severity there is no gender difference. In an attempt to explain these findings, one theory asserts that preadolescent women on average have more risk factors for depression when compared to men. These risk factors then combine with the typical stresses and challenges of adolescent development to trigger the onset of depression. Depression in youth and adolescence is associated with a wide array of outcomes that can come later in life for the affected individual. Some of these outcomes include poor physical and mental health, trouble functioning socially, and suicide. Suicidal intent
Like their adult counterparts, children and adolescent depression sufferers are at an increased risk of attempting or committing suicide. Suicide is the third leading cause of death among 15-to-19-year-olds. Adolescent males may be at an even higher risk of suicidal behavior when also presenting with a conduct disorder.
The diaphragmatic hernia found in the 8p23.1 deletion syndrome has not been found in the 8p23.1 duplication syndrome to date. The duplication may be associated with copy number changes of the adjacent olfactory receptor/defensin repeats (ORDRs) that predispose to the 8p23.1 deletion and duplication syndromes. High total copy numbers of these repeats have been associated with predisposition to psoriasis and low copy number with predisposition to Crohns disease. Genetics
The duplication includes ~3.75 Mb between the distal and proximal ORDRs at either end of band 8p23.1. The copy number of the adjacent repeats may also be altered. The 8p23.1 duplication syndrome cannot be distinguished using conventional cytogenetics from high level copy number variation of the repeats themselves.Both de novo cases and families with transmitted duplications from parents of both sex are known. The duplication is believed to arise de novo as a result of non-allelic homologous recombination (NAHR) between the proximal and distal ORDRs. NAHR is also thought to give rise to the reciprocal microdeletion syndrome, the polymorphic inversion between the ORDRs and a variety of other large scale abnormalities involving the short arm of chromosome 8. Diagnosis
Phenotypes
See also
Chromosome 8 (human)

References
External links

DECIPHER database description