LOTTA Terr CONTENTS Introduction Klinefelter syndrome (Description, signs and symptoms, cause, complications) Turner syndrome (Description, signs and symptoms, cause, complications) Down syndrome (Description, signs and symptoms, cause, complications) ConclusionLLLSLL LCL LAST Chromosomal abnormalities or chromosomal disorders are the type of genetic disorders caused due to the change in one or many chromosomes or the abnormal arrangement of the chromosomes. There are different types of chromosomal abnormalities that are as follows: e Aneuploidy — It is a condition in which there is a loss or gain of chromosomes due to abnormal segregation of genes during cell division. It can lead to monosomy, trisomy, tetrasomy, etc. Polyploidy — It is a condition in which the count of the entire set of chromosomes increases due to the failure of cytokinesis in cell division. It is mostly observed in plants. In humans, when there is an extra copy of a chromosome in one of the pairs, it is called trisomy and when one of the chromosomes from the pair is lacking, it is called monosomy.LETT LE LsLdALdA Ss F Y PIPL POPUEEEPIVIL ISD ES (1)Klinefelter syndrome Description: Klinefelter syndrome is a genetic condition that results hen a boy is born with an extra copy of the X chromosome. Klinefelter syndrome is a genetic condition affecting males, and it often sn't diagnosed until adulthood. Klinefelter syndrome may adversely affect testicular growth, resulting in smaller than normal testicles, which can lead to lower production of testosterone. The syndrome may also cause reduced muscle mass, reduced body and facial hair, and enlarged breast tissue. The effects of Klinefelter syndrome vary, and not everyone has the same signs and symptoms. Signs and symptoms: Signs and symptoms of Klinefelter syndrome vary widely among males with the disorder. Many boys with Klinefelter syndrome show few or only mild signs. The condition may go undiagnosed until adulthood or it may never be diagnosed. For others, the condition has a noticeable effect on growth or appearance. Signs and symptoms of Klinefelter syndrome also vary by age: 1.Babies Signs and symptoms may include: e Weak muscles e Slow motor development — taking longer than average to sit up, crawl and walk| SX Delay in speaking Problems at birth, such as testicles that haven't descended into the scrotum 2.Boys and teenagers Signs and symptoms may include: 3.Men Taller than average stature Longer legs, shorter torso and broader hips compared with other boys Absent, delayed or incomplete puberty After puberty, less muscle and less facial and body hair compared with other teens Small, firm testicles Small penis Enlarged breast tissue (gynecomastia) Weak bones Low energy levels Tendency to be shy and sensitive Difficulty expressing thoughts and feelings or socializing Problems with reading, writing, spelling or math Signs and symptoms may include: e Low sperm count or no sperm e Small testicles and penis ¢ Low sex drive ¢ Taller than average height « Weak bones e Decreased facial and body hairLILI LLLELE VEL VRAVRAPAP TTS rd Less muscular compared with other men e Enlarged breast tissue e Increased belly fat Causes Klinefelter syndrome occurs as a result of a random error that causes a male to be born with an extra sex chromosome. It isn't an inherited condition. Humans have 46 chromosomes, including two sex chromosomes that determine a person's sex. Females have two X sex chromosomes (XX). Males have an X and a Y sex chromosome (XY). Klinefelter syndrome can be caused by: e One extra copy of the X chromosome in each cell (XXY), the most common cause « An extra X chromosome in some of the cells (mosaic Klinefelter syndrome), with fewer symptoms e More than one extra copy of the X chromosome, which is rare and results in a severe form Extra copies of genes on the X chromosome can interfere with male sexual development and fertility.Complications Klinefelter syndrome may increase the risk of: e Anxiety and depression * Social, emotional and behavioral problems, such as low self- esteem, emotional immaturity and impulsiveness Infertility and problems with sexual function Weak bones (osteoporosis) Heart and blood vessel disease Breast cancer and certain other cancers ¢ Lung disease ¢ Metabolic syndrome, which includes type 2 diabetes, high blood pressure (hypertension), and high cholesterol and triglycerides (hyperlipidemia) Autoimmune disorders such as lupus and rheumatoid arthritis Tooth and oral problems that make dental cavities more likely Autism spectrum disorder c Frontal baldness - a s Poor beard e growth Narrow ~ ~ : ~ — x.(2)Turner syndrome Description: Turner syndrome, a condition that affects only females, hen one of the X chromosomes (sex chromosomes) is partially missing. Turner syndrome can cause a variety of and developmental problems, including short height, failure of s to develop and heart defects. syndrome may be diagnosed before birth (prenatally), during or in early childhood. Occasionally, in females with mild signs mptoms of Turner syndrome, the diagnosis is delayed until the young adult years. nd women with Turner syndrome need ongoing medical care ariety of specialists. Regular checkups and appropriate care elo most girls and women lead healthy, independent lives. Signs and symptoms: id symptoms of Turner syndrome may vary among girls and with the disorder. For some girls, the presence of Turner ome may not be readily apparent, but in other girls, several p al features are apparent early. Signs and symptoms can be subtle, developing slowly over time, or significant, such as heart Sa 1.Before birth rer syndrome may be suspected prenatally based on prenatal cell- DNA screening — a method to screen for certain chromosomal ormalities in a developing baby using a blood sample from the ther — or prenatal ultrasound, Prenatal ultrasound of a baby with Turner syndrome may show:‘luid collection on the back of the neck or other abnormal ections (edema) abnormalities ‘ormal kidneys 2.At birth or during infancy Wide or weblike neck ¢ Low-set ears ¢ Broad chest with widely spaced nipples ¢ High, narrow roof of the mouth (palate) ¢ Arms that turn outward at the elbows Fingernails and toenails that are narrow and turned upward Swelling of the hands and feet, especially at birth Slightly smaller than average height at birth ¢ Slowed growth * Cardiac defects Low hairline at the back of the head ¢ Receding or small lower jaw Short fingers and toes 3.In childhood, teens and adulthood most common signs in almost all girls, teenagers and young men with Turner syndrome are short stature and ovarian ciency due to ovarian failure. Failure of the ovaries to developbirth or gradually during childhood, the teen years or d. Signs and symptoms of these include: ¢ Slowed growth « No growth spurts at expected times in childhood ¢ Adult height significantly less than might be expected for a female member of the family Failure to begin sexual changes expected during puberty Sexual development that "stalls" during teenage years Early end to menstrual cycles not due to pregnancy e For most females with Turner syndrome, inability to conceive a child without fertility treatment Causes people are born with two sex chromosomes. Males inherit the X osome from their mothers and the Y chromosome from their s. Fernales inherit one X chromosome from each parent. In s who have Turner syndrome, one copy of the X chromosome is g, partially missing or changed. The genetic changes of Tumer syndrome may be one of the following: ® Monosomy. The complete absence of an X chromosome generally occurs because of an error in the father's sperm or in the mother's egg. This results in every cell in the body having only one X chromosome. © Mosaicism. In some cases, an error occurs in cell division during early stages of fetal development. This results in some cells in the body having two complete copies of the Xchromosome. Other cells have only one copy of the X chromosome. * X chromosome changes. Changed or missing parts of one of the X chromosomes can occur, Cells have one complete and one altered copy. This error can occur in the sperm or egg with all cells having one complete and one altered copy. Or the error can occur in cell division in early fetal development so that only some cells contain the changed or missing parts of one of the X chromosomes (mosaicism) © Y chromosome material. |n a small percentage of Turner syndrome cases, some cells have one copy of the X chromosome and other cells have one copy of the X chromosome and some Y chromosome material. These individuals develop biologically as female, but the presence of Y chromosome material increases the risk of developing a type of cancer called gonadoblastoma. Complications Turner syndrome can affect the proper development of several body systems, but this varies greatly among individuals with the syndrome. mplications that can occur include: Heart problems. Many infants with Turner syndrome are born with heart defects or even slight abnormalities in heart structure that increase their risk of serious- complications. Heart defects often include problems with the aorta, the large blood vessel that branches off the heart and delivers oxygen-rich blood to the body.* High blood pressure. Turner syndrome can increase the risk of high blood pressure — a condition that increases the risk of developing diseases of the heart and blood vessels. Hearing loss. Hearing loss is common with Turner syndrome. In some cases, this is due to the gradual loss of nerve function. An ncreased risk of frequent middle ear infections can also result in hearing loss. « Vision problems, An increased risk of weak muscle control of eye movements (strabismus), nearsightedness and other vision problems can occur with Turner syndrome. Kidney problems. Turner syndrome may be associated with malformations of the kidneys. Although these abnormalities generally don't cause medical problems, they may increase the risk of urinary tract infections. Autoimmune disorders. Turner syndrome can increase the risk of an underactive thyroid (hypothyroidism) due to the autoimmune disorder Hashimoto's thyroiditis. There is also an increased risk of diabetes. Sometimes Turner syndrome is associated with gluten intolerance (celiac disease) or inflammatory bowel disease. Skeletal problems. Problems with the growth and development of bones increase the risk of abnormal curvature of the spine (scoliosis) and forward rounding of the upper back (kyphosis). Turner syndrome can also increase the risk of developing weak, brittle bones (osteoporosis) Learning disabilities. Girls and women with Turner syndrome usually have normal intelligence. However, there is increased risk of learning disabilities, particularly with learning that involves spatial concepts, math, memory and attention.« Mental health issues. Girls and women with Turner syndrome may have challenges functioning in social situations, may experience anxiety and depression, and may have an increased risk of attention-deficit/hyperactivity disorder (ADHD). © Infertility. Most females with Turner syndrome are infertile. However, a very small number may become pregnant spontaneously, and some can become pregnant with fertility treatment. Short stature Low posterior Webbing of neck airing: Broad chest and widely spaced nipples Coarctation of aorta Cubitus valgus Streak ovaries, infortuity. Pigmented nevi . amenorrhea Peripheral lymphedema at birth (3) Down syndrome: Description: Down syndrome is a genetic disorder caused when abnormal cell division results in an extra full or partial copy of chromosome 21. This extra genetic material causes the developmental changes and physical features of Down syndrome.Down syndrome varies in severity among individuals, causing lifelong ual disability and developmental delays. It's the most common chromosomal disorder and cause of learning disabilities in ‘en. It also commonly causes other medical abnormalities, cluding heart and gastrointestinal disorders. Signs and symptoms: A person with Down syndrome is an individual — intellectual and elopmental problems may be mild, moderate or severe. Some oeople are healthy while others have significant health problems such s serious heart defects. Children and adults with Down syndrome have distinct facial features. Though not all people with Down syndrome have the same features, some of the more common features include:- Flattened face ¢ Small head Short neck Protruding tongue ¢ Upward slanting eye lids (palpebral fissures) e Unusually shaped or small ears « Poor muscle tone Broad, short hands with a single crease in the palm e Relatively short fingers and small hands and feet ¢ Excessive flexibility © Tiny white spots on the colored part (iris) of the eye called Brushfield's spotsPRLIVVTVVVLLLLLAIL AVP LLIELLPLOLLLY e Short height Infants with Down syndrome may be average size, but typically they grow slowly and remain shorter than other children the same age. Causes Human cells normally contain 23 pairs of chromosomes. One chromosome in each pair comes from your father, the other from your mother. Down syndrome results when abnormal cell division involving chromosome 21 occurs. These cell division abnormalities result in an extra partial or full chromosome 21. This extra genetic material is responsible for the characteristic features and developmental problems of Down syndrome. Any one of three genetic variations can cause Down syndrome: Trisomy 21. About 95 percent of the time, Down syndrome is caused by trisomy 21 — the person has three copies of chromosome 21, instead of the usual two copies, in all cells This is caused by abnormal cell division during the development of the sperm cell or the egg cell. ¢ Mosaic Down syndrome. |n this rare form of Down syndrome, a person has only some cells with an extra copy of chromosome 21. This mosaic of normal and abnormal cells is caused by abnormal cell division after fertilization ¢ Translocation Down syndrome. Down syndrome can also occur when a portion of chromosome 21 becomes attached (translocated) onto another chromosome, before or atDIVIPPIVIVIIINI adults with Down syndrome are at greater risk of obstructive sleep apnea Obesity. People with Down syndrome have a greater tendency to be obese compared with the general population. Spinal problems. Some people with Down syndrome may have a misalignment of the top two vertebrae in the neck (atlantoaxial instability). This condition puts them at risk of serious injury to the spinal cord from overextension of the neck. Leukemia. Young children with Down syndrome have an increased risk of leukemia. ee ey aa eyes with skin pease eee rtd picehpaclactis nits Seas - rs eee Reeth short, stocky buildConclusion c diseases can be controlled best through an integrative ‘coach of community education, population screening, genetic unseling, carrier identification and neonatal screening. |GDD would provide a key platform for clinicians, epidemiologists, geneticists and genetic counselors to access a central genetic data-source for the ndian population. This centralized mutation database is likely to play a aluable role in correlation of genotype with phenotype. We think that over long time, with enrichment of the database, the benefits accrued from it would apply to other countries (e.g. Pakistan, Bangladesh, Srilanka, Bhutan and Nepal) of the Indian subcontinent that share historically similar population groups divided by political boundaries. In addition, such implication is more directly applicable to the nonresident Indians across the world migrated in relatively recent past. Reference link - https: //www.britannica.com/science/chromosomal-disorder https://en.m,wikipedia.org/wiki/Chromosome abnormality https:/hwww.vedantu.com/biology/chromosomal-disorders-in-humans https:www.qooale.comfurl?sa=t&source=web&ret=|&urlshttps://byjus.comineet/chromosomal-disorder-in- humans/&ved=2ahUKEwixirv@acb4AhXHQPUHHVDEB 8QFnoECFMOAQ&usc=AOvVaw3aP_GGBsXPFtFWTpdsBt4-