On 19 January 2018, the medical examiner-coroner for the county of Los Angeles said musician Tom Petty died from an accidental drug overdose as a result of mixing medications that included fentanyl, acetyl fentanyl, and despropionyl fentanyl (among others). He was reportedly treating "many serious ailments" that included a broken hip. In 2018, American rapper Mac Miller died from an accidental overdose of fentanyl, cocaine and alcohol. On 16 December 2018, American tech entrepreneur Colin Kroll, founder of social media video-sharing app Vine and quiz app HQ Trivia, died from an overdose of fentanyl, heroin, and cocaine. On 1 July 2019, American baseball player Tyler Skaggs died from pulmonary aspiration while under the influence of fentanyl, oxycodone, and alcohol. On 1 January 2020, American rapper, singer, and songwriter Lexii Alijai died from accidental toxicity resulting from the combination of alcohol and fentanyl. On 20 August 2020, American singer, songwriter and musician Justin Townes Earle died from an accidental overdose caused by cocaine laced with fentanyl. On 24 August 2020, Riley Gale, frontman for the Texas metal band Power Trip, died as a result of the toxic effects of fentanyl in a manner that was ruled accidental. On 22 April 2021, Digital Underground frontman, rapper, and musician Shock G died from an accidental overdose of fentanyl, meth, and alcohol. On 6 September 2021, actor Michael K. Williams, who rose to fame through his critically acclaimed role as Omar Little on the HBO drama series The Wire, died from an overdose of fentanyl, parafluorofentanyl, heroin, and cocaine.
When aneuploidy is detected in a fraction of cells in an individual, it is called chromosomal mosaicism. In general, individuals who are mosaic for a chromosomal aneuploidy tend to have a less severe form of the syndrome compared to those with full trisomy. For many of the autosomal trisomies, only mosaic cases survive to term. However, mitotic aneuploidy may be more common than previously recognized in somatic tissues, and aneuploidy is a characteristic of many types of tumorigenesis (see below). Mechanisms
Aneuploidy arises from errors in chromosome segregation, which can go wrong in several ways.Nondisjunction usually occurs as the result of a weakened mitotic checkpoint, as these checkpoints tend to arrest or delay cell division until all components of the cell are ready to enter the next phase. For example, if a checkpoint is weakened, the cell may fail to notice that a chromosome pair is not lined with the spindle apparatus. In such a case, most chromosomes would separate normally (with one chromatid ending up in each cell), while others could fail to separate at all. This would generate a daughter cell lacking a copy and a daughter cell with an extra copy.Completely inactive mitotic checkpoints may cause nondisjunction at multiple chromosomes, possibly all. Such a scenario could result in each daughter cell possessing a disjoint set of genetic material.Merotelic attachment occurs when one kinetochore is attached to both mitotic spindle poles. One daughter cell would have a normal complement of chromosomes; the second would lack one.