From the Genesis of Down syndrome: What we know and what we stll need to
know
Abdul-rahmon Adewuyi Olagunju
1*
and Mustapha Akajewole Masud
2,3
1
Department of Physiology, Federal University of Technology, Akure, Nigeria
2
Department of Human Anatomy, School of Health and Medical Sciences, State University of Zanzibar, Zanzibar, Tanzania
3
Department of Clinical Anatomy, School of Laboratory Medicine and Medical Sciences, College of Health Sciences, Westville Campus, University of
KwaZulu-Natal, Durban, South Africa
*
Corresponding author: Olagunju ARA, Department of Physiology, Federal University of Technology, Akure, Nigeria, E-mail:
olagunjuabdulrahman3@gmail.com
Citation: Olagunju ARA, Masud MA (2021) From the Genesis of Down Syndrome: What we know and what we still need to know. Clin
Psychiatry Vol.7 No. 1:77.
Received date: December 19, 2020; Accepted date: January 4, 2021; Published date: January 11, 2021
Abstract
Despite years of intensive studies on DS, the clinical
importance and recent understanding between the
syndrome and maternal age, paternal age, habitual and
environmental risk factors are relatvely identfed. Studies
indicated that the vast majority of errors leading to trisomy
21 are due to errors in the egg, as nearly 90% of cases
involve an additonal maternal chromosome. There are
many cases that the maternal is not prone to these risk
factors but stll by chance give birth to a child with DS.
However, this can be atributed to altered chromosomal
recombinaton.
Today, technology has helped in the diagnosis of this
anomaly with the inventon of next-generaton sequencing
technologies which enabled testng of multple disease
genes simultaneously, ranging from targeted gene panels to
Exome Sequencing (ES) and Genome Sequencing (GS). A
growing number of studies demonstrate that GS can detect
an unparalleled range of pathogenic abnormalites in a
single laboratory workfow. GS has the potental to deliver
unbiased, rapid and accurate molecular diagnoses to
patents across diverse clinical indicatons and complex
presentatons, but the prognosis of DS remains enigma.
Most studies argued that pregnant women diagnosed of DS
has the choice to either terminate or contnue with the
pregnancy, in which 90% usually terminate the pregnancy
even before the general public notce. This shows there's
stll a lot to do on the prognosis. This review suggests ways
with the inventon of technology how this anomaly can be
treated immediately afer the diagnosis.
Keywords: Aneuploidy; Down Syndrome (DS); Exome
Sequencing (ES); Genome Sequencing (GS)
History
Victor A. McKusick in his recently edited artcle on Down
syndrome told some tales on DS where he referenced [1] who
frst reported the associaton between Down syndrome and
heart malformaton. Abbot [2] who drew atenton to the
associaton between Atrioventricular Septal Defect (AVSD) and
Down Syndrome (DS). Also, Neri et al. [3] provided a detailed
review of the history of the scientfc developments leading to
the molecular characterizaton of DS.
Speculaton about the historic prevalence of DS has included
references to apparent depictons of the syndrome in 15th [4]
and 16th [5] century paintngs. Martnez-Frias [6] reported what
seems likely to be the earliest evidence of the syndrome in a
terra-cota head from approximately 500 AD belonging to the
Tolteca culture of Mexico, in which 'it is easy to identfy the short
palpebral fssures, oblique eyes, midface hypoplasia, and open
mouth with macroglossia, fndings that clearly defne the face of
a person with DS.
Bernal and Briceno [7] examined potery artfacts from the
Tumaco-La Tolita culture, which existed on the border of
present-day Colombia and Ecuador approximately 2,500 years
ago, and described several fgurines with characteristcs
suggestve of DS. Bernal and Briceno [7] believed these artfacts
to be among the earliest artstc representatons of disease.
Introducton
The whole journey started in 1866 when John Langdon Down
initally identfed DS approximately 153 years ago [8]. DS is the
genetc manifestaton of trisomy of chromosome 21 [9]. DS is a
genetc disorder caused when abnormal cell division results in
an extra full or partal copy of chromosome 21. This extra
genetc material in turn causes the developmental changes and
physical features of Down syndrome.
The body been made up of trillions of somatc cells with the
capacity to divide into identcal daughter cells facilitatng
organismal growth, repair, and response to the changing
environment known as “mitosis.” and its counterpart in the
gametes, a diferent form of cell division also occurs called
“meiosis.” The outcome of meiosis is the creaton of daughter
cells, either sperm or egg cells, through reducton division which
results in a haploid complement of chromosomes so that on
Review Article
iMedPub Journals
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Clinical Psychiatry
ISSN 2471-9854
Vol.7 No.1:77
2021
© Copyright iMedPub | This article is available from: https://clinical-psychiatry.imedpub.com/
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