What Causes a Baby to Have an Enlarged Skull and Developmental Problems Extra Chromosome

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• Chromosome 1
• Chromosome ii
• Chromosome iii
• Chromosome four
• Chromosome 5
• Sex-linked chromosomes - X chromosome
• Sex-linked chromosomes - Y chromosome

Chromosomes are thread-similar structures that hold genes, which are fragments of Deoxyribonucleic acid that behave the hereditary data of an individual.

Chromosomes are comprised of ii segments or arms separated past a region known as the centromere. The longer arm is called the "q" arm, and the shorter arm is designated as the "p" arm. A typical human cell consists of 23 pairs of chromosomes, which add up to a total of 46 chromosomes per cell. The first 22 pairs of chromosomes are chosen autosomes, and the last pair is called the sex chromosomes – they decide the sex of an individual. The mother and father each pass on one set of 22 autosomes and ane sex chromosome to their offspring. Females have 2 X chromosomes (XX), and males take one Ten and ane Y chromosome (XY).

Disorders acquired past chromosomal abnormalities can exist either numerical or structural.

• A numerical disorder occurs when there is a alter in the number of chromosomes. Downwardly syndrome is a well-known case of a numerical disorder (three copies of chromosome 21).
• A structural abnormality results from alterations in the structure of the chromosome. Structural abnormalities may lead to a difference in the number of genes, which cause various clinical differences in afflicted individuals. Deletions, duplications, translocations, inversions, and rings are some of the structural abnormalities, which may lead to chromosomal disorders.

In humans, each jail cell normally contains 22 pairs of autosomes and i pair of sex chromosomes, X and Y, in male. - Illustration Credit: Soleil Nordic / Shutterstock

Chromosome i

Chromosome 1 is the largest of the 23 chromosomes and consists of approximately iv,220 genes, which accounts for nearly 8% of the entire human DNA.

Chromosome 1 is highly susceptible to genetic variations such as polymorphisms or mutations, and a plethora of diseases have been linked to these abnormalities. Structural or numerical abnormalities of chromosome 1 cause the following disorders.

1p36 deletion syndrome

1p36 deletion syndrome is caused by a deletion of genetic cloth from the short arm or p arm of chromosome 1. The condition affects approximately i in 5,000 newborns and is the almost common final chromosomal deletion in humans. The signs and symptoms depend on the extent of the deletion, which varies amid the affected individuals. Some common signs of this syndrome include distinctive facial features, delay in development, intellectual disability, seizures, vision and hearing problems, congenital centre defects, and renal abnormalities.

Neuroblastoma

Neuroblastomas are cancers that initiate in immature nerve cells chosen neuroblasts. Deletions, inside part of the brusque arm of chromosome 1 (1p36) are associated with the development of neuroblastoma. Researchers believe the deleted genetic portions normally contain a tumor suppressor cistron; nonetheless, the verbal mechanism which these genes play in cancer initiation and progression is not known.

Neuroblastoma cells: nuclei are stained in red, microfilaments are in green and in blue. Image Credit: Vshivkova / Shutterstock

1q21.ane microdeletion

1q21.one microdeletion involves a change in a small piece of the long arm or q arm of chromosome 1. The exact size of the deleted region varies; however, most cases involve around 1.35 one thousand thousand missing Deoxyribonucleic acid base pairs. Individuals with 1q21.ane microdeletion present with development delays, limitations in brain functioning, physical anomalies, and psychiatric bug; however, in some cases the patients are asymptomatic.

1q21.1 duplication syndrome

1q21.1 duplication syndrome is a chromosomal disorder acquired past duplication of a small slice of chromosome 1. The syndrome is characterized past features such as big head size, developmental delay, intellectual disabilities, typical facial features, cardiac issues, and seizures. This condition tin occur spontaneously or tin can be inherited.

Thrombocytopenia-absent-minded radius (TAR) syndrome

Thrombocytopenia-absent radius (TAR) syndrome is a rare condition in which thrombocytopenia or low blood platelet count occurs with radial aplasia - a congenital defect characterized past abnormal forearms caused past the absence of radius bone. Most cases of TAR syndrome involve a deletion in the 1q21.1 region of chromosome ane.

Chromosome two

Chromosome 2 is the second largest chromosomes constitute in human cells. Abnormalities of chromosome 2 crusade the following chromosomal disorders.

2q37 deletion syndrome

2q37 deletion syndrome is a rare genetic disorder caused by the deletion of genes, at a location 2q37 of the long arm of chromosome 2. Developmental problems, intellectual and adaptive behavior bug, obesity, and bone deformities are some mutual signs of this condition.

Cancers

Chromosome 2 abnormalities also cause cancers such as myeloid malignancies. These abnormalities are ordinarily somatic, which are not inherited, only rather caused during a person's lifetime. Translocation or rearrangement of genetic textile betwixt chromosomes 2 and 3 has been held responsible for the development of myeloid malignancies.

Myelodysplastic syndrome is another status which occurs due to chromosome 2 abnormalities. The disease affects the blood and bone marrow condition and is characterized past trisomy ii; in which cells take an extra re-create of chromosome 2 than the usual 2. Anemia is ofttimes plant in people with this syndrome.

MBD5-associated neurodevelopmental disorder (MAND)

MBD5-associated neurodevelopmental disorder (MAND) is a congenital status which leads to abnormal neurological and physical development. MAND is acquired by deletion or duplication of chromosome 2 at position q23.1. MAND patients take concrete deformities and intellectual disability. They too have delayed development, impaired speech, and behavioral problems.

SATB2-associated syndrome

The SATB2-associated syndrome leads to developmental delay, intellectual and behavior problems, head and face anomalies. Speech bug and dental abnormalities also occur in individuals with this syndrome. Alterations of the SATB2 gene are acquired past changes on the q arm of chromosome 2

Band chromosome

Ring chromosome is a chromosome 2 abnormality. They develop when breaks at the ends of the chromosome, join together to form a circular ring-like structure. The disorder causes developmental delay, microcephaly or small-scale head, retarded growth, heart defects, and facial anomalies.

Chromosome 3

Chromosome 3 is the 3rd largest chromosomes in humans, which makes up around vii% of the genetic fabric in the whole genome. Chromosome 3 has gene clusters that code for the receptors involved in the sense of smell and inflammatory processes. Following are some of the chromosome 3 abnormalities.

3p deletion syndrome

3p deletion syndrome is caused by deletion of genetic matter from the terminate of the small arm of chromosome 3. Intellectual problems, delayed development, and physical abnormalities are some features associated with this syndrome.

3q29 microdeletion syndrome

3q29 microdeletion syndrome involves the deletion of a small piece of chromosome 3 in each cell. Individuals with 3q29 microdeletion accept delayed development; intellectual, behavioral and psychiatric disorders, and physical anomalies.

3q29 microduplication syndrome

As the name suggests, the 3q29 microduplication syndrome is caused due to duplication of a small-scale slice of chromosome 3 in each jail cell. Signs and symptoms associated with this syndrome include delayed evolution and learning problems, vision problems, cardiac defects, and microcephaly.

Articulate prison cell renal carcinoma

Clear cell renal carcinoma is associated with alterations in chromosome 3. The cancer may involve deletion of function of the p arm or translocations of genetic information or a missing chromosome copy. The changes associated with clear prison cell renal carcinoma are not inherited and are sporadic.

Chromosome iv

Chromosome 4 chromosome represents around 6.5% of the Deoxyribonucleic acid in the man genome and comprises nearly k genes. Following are some disorders caused by chromosome 4 abnormalities.

Facioscapulohumeral muscular dystrophy

Facioscapulohumeral muscular dystrophy is a muscular disorder caused by hypomethylation of the D4Z4 region in the q arm of chromosome 4. Muscle weakness and muscle atrophy are two characteristic features of this disorder. The condition affects muscles of the face up, arms, and shoulders. In some cases, the muscles around the optics may also be afflicted.

Wolf-Hirschhorn syndrome

Wolf-Hirschhorn is a complex syndrome acquired by the deletion of genetic material at a region termed 4p16.3 in the short arm of chromosome four. The deleted part contains key genes required for normal growth and evolution; hence, Wolf-Hirschhorn syndrome is characterized by halted growth, intellectual disabilities, facial abnormalities, and seizures.

Cancers

Chromosome 4 abnormalities are also associated with cancers such as leukemia, multiple myeloma. Translocation or rearrangement of genetic material is held responsible for the development of these cancers.

PDGFRA-associated chronic eosinophilic leukemia is acquired by alterations in the PDGFRA gene, which is located on chromosome 4. This condition is characterized past an increase in the number of eosinophils, which are a blazon of white blood cells involved in allergic reactions.

Chromosome 5

Chromosome 5 constitutes nearly 6% of the total Deoxyribonucleic acid. Chromosome 5 has a depression gene density as nearly of its parts take non-coding gene regions. Chromosome 5 also has genes that code for interleukins, which are modulators of allowed response.

Cri-du-Chat syndrome and familial adenomatous polyposis are two atmospheric condition which are acquired by deletions in chromosome 5.

Cri-du-chat syndrome

Cri-du-chat syndrome involves deletion in the short arm of chromosome v. The status is characterized by true cat-like cry and microcephaly or small caput.

Periventricular heterotopia

Periventricular heterotopia is a brain malformation caused by abnormal duplication of certain parts of chromosome 5. The disorder is characterized by abnormal neuronal migration, which leads to the accumulation of neuronal clumps or nodules effectually fluid-filled cavities.

Acute myeloid leukemia (AML) and Myelodisplastic syndrome (MDS)

Deletions in the long arm of chromosome 5 are oftentimes found in cancers such as astute myeloid leukemia (AML) and myelodisplastic syndrome (MDS).

Familial adenomatous polyposis

Familial adenomatous polyposis is caused by a deletion of region coding for adenomatous polyposis coli, a tumor suppressor protein, on the long arm of chromosome v. Formation of inactive adenomatous polyposis coli leads to leads to polyps germination in the rectum and colon. Polyps are non-malignant growths, which have a high propensity to develop into cancer.

5q31.3 microdeletion syndrome

5q31.three microdeletion syndrome is caused by the deletion of a modest piece of chromosome 5. The condition causes impaired speech and walking, low muscle tone or hypotonia, breathing problems, seizures, and facial abnormalities. Loss of the PURA gene is held responsible for most of the symptoms. Pur-alpha, the protein encoded past the PURA gene is required for normal growth or neurons.

Sex-linked chromosomes - X chromosome

X chromosome and the Y chromosome are the sexual activity chromosomes in humans. The X chromosome represents v% of the total DNA in women and nigh two.5% of the total Deoxyribonucleic acid in men. Mutations in the X chromosomes pb to several genetic disorders.

Klinefelter syndrome

Klinefelter syndrome occurs in males who have one or more extra copies of the Ten chromosome. Individuals with this disorder take abnormal sexual development, with dumb testes evolution and reduced testosterone levels. They take reduced muscle forcefulness and decreased intellectual and motor skills. Infertility is also mutual.

Triple Ten syndrome

Triple X syndrome or trisomy Ten is caused by an extra re-create of the 10 chromosome in females. Females with triple Ten syndrome take an increased risk of delayed development of language, motor, and cerebral skills. Even though the patients accept normal fertility, issues of premature ovarian failure are quite mutual.

Turner syndrome

Turner syndrome is observed in females with a missing or abnormally structured Ten chromosome. The patients take brusque stature and have gonadal dysgenesis or defective gonads. Individuals with this syndrome have complications such as heart defects, os deformities, hearing and vision problems, and kidney anomalies.

Intestinal pseudo-obstruction

Intestinal pseudo-obstruction is characterized by impairment in peristalsis – the muscle contractions that propel food through the gastrointestinal tract. The condition is caused past mutations, duplications, or deletions of the FLNA cistron and the genes adjacent to the X chromosome. Intestinal pseudo-obstruction leads to aggregating of incompletely digested food in the intestines, which causes abdominal distention, pain, nausea, vomiting, and constipation or diarrhea. The condition also leads to loss of appetite and dumb absorption of nutrients.

Microphthalmia with linear skin defects syndrome

Microphthalmia with linear pare defects syndrome is acquired by deletion of a region called Xp22 on the 10 chromosome. Microphthalmia or aberrant eyes and linear skin lesions (face up and neck) are some characteristic features of the condition.

X-linked acrogigantism

Ten-linked acrogigantism involves duplication of GPR101 cistron on the X chromosome. The condition is characterized by an enlarged pituitary gland and evolution of pituitary adenoma. Abnormalities in the pituitary gland atomic number 82 to the excessive release of growth hormone, which, in plow, leads to rapid growth in the patients.

Sex activity-linked chromosomes - Y chromosome

The following chromosomal conditions are associated with abnormalities of the Y chromosome.

46,Twenty testicular disorder of sex activity evolution

46,XX testicular disorder of sex development is caused by translocation of the SRY gene - which is usually located on the Y chromosome, onto the Ten chromosome. Individuals with this disorder develop as a male despite not having a Y chromosome. They take small testes and develop gynecomastia. These individuals are infertile due to lack of sperm and take wellness issues related to depression testosterone levels.

47,XYY syndrome

47,XYY syndrome is found in males with an actress Y chromosome in each cell. The condition causes learning disabilities, delayed speech development, and low musculus tone. Individuals with this syndrome are besides taller than expected.

48,XXYY syndrome

48,XXYY syndrome develops in males with an extra X chromosome and an actress Y chromosome. The syndrome is characterized by infertility, insufficient testosterone production, cognitive and behavioral impairments, developmental delays, and an increased chance of congenital abnormalities.

Y chromosome infertility

Y chromosome infertility is characterized past azoospermia or lack of sperm cells. The status is acquired past the deletion of genetic material in areas known as the azoospermia factor or AZF region.

Sources

• National Human Genome Research Plant. Chromosome Abnormalities Fact Sail. www.genome.gov/.../Chromosome-Abnormalities-Fact-Sheet
• U.S National Library of Medicine. (2019). Chromosome ane. Health Conditions Related to Chromosomal Changes. https://ghr.nlm.nih.gov/chromosome/ane#conditions
• U.South National Library of Medicine. (2019). Chromosome 2. Wellness Conditions Related to Chromosomal Changes. https://ghr.nlm.nih.gov/chromosome/2#conditions
• U.Southward National Library of Medicine. (2019). Chromosome three. Health Conditions Related to Chromosomal Changes. https://ghr.nlm.nih.gov/chromosome/3#weather condition
• U.S National Library of Medicine. (2019). Chromosome 4. Health Atmospheric condition Related to Chromosomal Changes. https://ghr.nlm.nih.gov/chromosome/four#conditions
• U.S National Library of Medicine. (2019). Chromosome 5. Health Conditions Related to Chromosomal Changes. https://ghr.nlm.nih.gov/chromosome/5#weather condition
• U.S National Library of Medicine. (2019). Chromosome X. Health Conditions Related to Chromosomal Changes. https://ghr.nlm.nih.gov/chromosome/10#conditions
• U.South National Library of Medicine. (2019). Chromosome Y. Wellness Weather condition Related to Chromosomal Changes. https://ghr.nlm.nih.gov/chromosome/Y#weather condition
• Jordan, V. K., et al. (2015). 1p36 deletion syndrome: an update. The application of clinical genetics. doi:10.2147/TACG.S65698
• Zarate, Y. A., & Fish, J. L. (2017). SATB2-associated syndrome: Mechanisms, phenotype, and practical recommendations. American periodical of medical genetics. Part A. doi:10.1002/ajmg.a.38022

Farther Reading

• All Chromosome Content
• What is a Chromosome?
• Chromosome 5 Chromosomal Conditions
• Chromosome History
• Chromosomes in Eukaryotes

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Source: https://www.news-medical.net/health/Common-Chromosomal-Disorders-(Chromosomes-1-5-and-X-and-Y).aspx

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