XXXXY syndrome
| 49,XXXXYsyndrome | |
|---|---|
| Specialty | Medical genetics  |
49,XXXXY syndrome is an extremely rare aneuploidic sex chromosomal abnormality. It occurs in approximately 1 out of 85,000 to 100,000 males.[1][2][3] This syndrome is the result of maternal non-disjunction during both meiosis I and II.[4] It was first diagnosed in 1960 and was coined Fraccaro syndrome after the researcher.[2]
Signs and symptoms[edit]
The symptoms of 49,XXXXY are slightly similar to those of Klinefelter syndrome and 48,XXXY, but they are usually much more severe. Aneuploidy is often fatal, but there is "X-inactivation", where the effect of the additional gene dosage due to the presence of extra X chromosomes is greatly reduced.[5]
Reproductive[edit]
Those with 49,XXXXY syndrome tend to exhibit infantile secondary sex characteristics with sterility in adulthood.[5]
- Hypoplastic genitalia[5]
Physical[edit]
Males with 49,XXXXY tend to have numerous skeletal anomalies. These skeletal anomalies include:[citation needed]
- Genu valgum
- Pes cavus
- Fifth finger clinodactyly
The effects also include:
- Cleft palate
- Club feet
- Respiratory conditions
- Short or/and broad neck
- Low birth weight
- Hyperextensible joints
- Short stature
- Narrow shoulders
- Coarse features in older age
- Hypertelorism
- Epicanthal folds
- Prognathism
- Gynecomastia (rare)
- Muscular hypotonia
- Cryptorchidism
- Congenital heart defects
- A very round face in infancy[5]
Cognitive and developmental[edit]
Much like Down syndrome, the mental effects of 49,XXXXY syndrome vary. Impaired speech and maladaptive behavioral problems are typical.[6] One study looked at males that were diagnosed with 48,XXYY, 48,XXXY and 49,XXXXY. They found that males with 48,XXXY and 49,XXXXY function at a much lower cognitive level than males their age. These males also tend to exhibit more immature behavior for their chronological age; increased aggressive tendencies were also cited in this study.[6]
Pathophysiology[edit]
As its name indicates, a person with the syndrome has one Y chromosome and four X chromosomes on the 23rd pair, thus having forty-nine chromosomes rather than the normal forty-six. As with most categories of aneuploidy disorders, 49,XXXXY syndrome is often accompanied by intellectual disability. It can be considered a form or variant of Klinefelter syndrome (47,XXY).[7] Individuals with this syndrome are typically mosaic, being 49,XXXXY/48, XXXX.[4]
It is genetic but not hereditary, meaning that while the genes of the parents cause the syndrome, there is a small chance of more than one child having the syndrome. The probability of inheriting the disease is about one percent.[5]
Diagnosis[edit]
49,XXXXY can be clinically diagnosed through karyotyping.[8] Facial dysmorphia and other somatic abnormalities may be reason to have the genetic testing done.[4]
Treatment[edit]
While there is no treatment to correct the genetic abnormality of this syndrome, there is the potential to treat the symptoms. As a result of infertility, one man from Iran used artificial reproductive methods.[4] An infant in Iran diagnosed with 49,XXXXY syndrome was born with patent ductus arteriosus, which was corrected with surgery, and other complications that were managed with replacement therapy.[4]
See also[edit]
- Aneuploidy
- Turner syndrome
- Klinefelter syndrome
- 49, XXXXX, a similar syndrome that affects females
References[edit]
- ^ Visootsak J, Graham JM (2006). "Klinefelter syndrome and other sex chromosomal aneuploidies". Orphanet J Rare Dis. 1: 42. doi:10.1186/1750-1172-1-42. PMC 1634840. PMID 17062147.
- ^ a b Fraccaro, M.; Kaijser, K.; Lindsten, J. (1960-10-22). "A child with 49 chromosomes". Lancet. 2 (7156): 899–902. doi:10.1016/s0140-6736(60)91963-2. ISSN 0140-6736. PMID 13701146.
- ^ Etemadi, Katayoon; Basir, Behnaz; Ghahremani, Safieh (March 2015). "Neonatal diagnosis of 49, XXXXY syndrome". Iranian Journal of Reproductive Medicine. 13 (3): 181–184. ISSN 1680-6433. PMC 4426158. PMID 26000009.
- ^ a b c d e Hadipour, Fatemeh; Shafeghati, Yousef; Bagherizadeh, Eiman; Behjati, Farkhondeh; Hadipour, Zahra (2013). "Fraccaro syndrome: report of two Iranian cases: an infant and an adult in a family". Acta Medica Iranica. 51 (12): 907–909. ISSN 1735-9694. PMID 24442548.
- ^ a b c d e Webspawner.com article on 49,XXXXY syndrome Archived 2008-09-14 at the Wayback Machine. Retrieved 26 March 2008.
- ^ a b Visootsak J, Rosner B, Dykens E, Tartaglia N, Graham JM (June 2007). "Behavioral phenotype of sex chromosome aneuploidies: 48,XXYY, 48,XXXY, and 49,XXXXY". Am. J. Med. Genet. A. 143A (11): 1198–203. doi:10.1002/ajmg.a.31746. PMID 17497714. S2CID 25732790.
- ^ Cotran, Ramzi S.; Kumar, Vinay; Fausto, Nelson; Nelso Fausto; Robbins, Stanley L.; Abbas, Abul K. (2005). Robbins and Cotran pathologic basis of disease. St. Louis, Mo: Elsevier Saunders. p. 179. ISBN 0-7216-0187-1.
- ^ Blumenthal, Jonathan D.; Baker, Eva H.; Lee, Nancy Raitano; Wade, Benjamin; Clasen, Liv S.; Lenroot, Rhoshel K.; Giedd, Jay N. (2013). "Brain morphological abnormalities in 49,XXXXY syndrome: A pediatric magnetic resonance imaging study". NeuroImage: Clinical. 2: 197–203. doi:10.1016/j.nicl.2013.01.003. PMC 3649771. PMID 23667827.
Further reading[edit]
- Jonathan D. Blumenthal; Eva H. Baker; Nancy Raitano Lee; Benjamin Wade; Liv S. Clasen; Rhoshel K. Lenroot; Jay N. Giedd (2013). "Brain morphological abnormalities in 49,XXXXY syndrome: A pediatric magnetic resonance imaging study". NeuroImage: Clinical. 2: 197–203. doi:10.1016/j.nicl.2013.01.003. PMC 3649771. PMID 23667827.