Human chromosomal Abnormalities ppt

Chromosomal abnormalities. 1. CHROMOSOMAL ABNORMALITIESPRESENTED BY:DR. BISWAJEETA SAHA (PGT,1ST YR),MODERATOR-DR.A.K.ADHYA (ASST. PROF),DEPT OFPATHOLOGY,KIMS,BBSR. 2. NORMAL KARYOTYPE Karyotype: a picture of the chromosomes from a single cell. 4. NUMERICAL ABNORMALITIES Euploid-any exact multiple of haploid Aneuploidy-chromosome compliment. Chromosomal Disorders 1. CHROMOSOMAL DISORDERS By -Lovnish Thakur ASU2014010100099 Integrated Biotech- 3rd sem Subject- Genetics 2. WHAT ARE CHROMOSOMAL DISORDERS • A chromosomal disorder occurs when there is a change in the number or structure of the chromosomes Human Karyotypes and Chromosomal Disorders - Human Karyotypes and Chromosomal Disorders The incidence of the syndrome is estimated as 1 in 3,000 live births. The PowerPoint PPT presentation: Chromosomal abnormalities is the property of its rightful owner

4. Chromosomal Anomalies = Missing, extra, or irregular portion of chromosomal DNA. Most foetus with some chromosomal abnormality do not survive. Affects approximately 1 out of 200 of new- borns. Karyotype = Full set of chromosomes from an individual Chromosome Abnormalities I. Chromosome Terms A. Autosome chromosomes that are not involved in determining the sex (gender) of an individual. - A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: 5c4696-YTZj

Chromosomal Disorders - SlideShar

  1. Chromosomal Abnormalities PPT and PDF Free To Download: A body abnormality, disorder, anomaly, aberration, or mutation may be a missing, extra, or irregular portion of body desoxyribonucleic acid.It is from an atypical range of chromosomes or a structural abnormality in one or additional chromosomes
  2. Chapter 15: Chromosomal Abnormalities 1. Define: nondisjunction polyploidy aneupoidy trisomy monosomy 2. Describe each of the aneuploidies that can be found in an appreciable number of human adults (chromosomal abnormality, common name of the syndrome if it has one, phenotypes) 3
  3. chromosomal aberrations (that explain chromosomal structure abnormalities). Chromosomal disorders form a category of human genetic diseases, that are manifested by developmental and reproductive abnormalities, as well as playing an important role in the pathogenesis of malignancy. Chromosomal abnormalities may be produced by
  4. chromosomes, karyotyping for prenatal and postnatal diagnoses, including the sources of cells used. • Explain the differences between the three prenatal diagnosis techniques. • Learn the terms used to describe the abnormalities in chromosomal numbers: polyploidy, aneuploidy: trisomy and monosomy, and mosiacism and their causing mechanisms
  5. Abnormalities in chromosomal number polyploidy -complete extra sets (3n, etc.) - fatal in humans, most animals aneuploidy -missing one copy or have an extra copy of a single chromosome three copies of a chromosome in your somatic cells: trisomy one copy of a chromosome in your somatic cells: monosomy most trisomies and monosomies are lethal wel
  6. Human Karyotype ( Chromosomes) 1. Karyotype. 2. Karyotype Definition: A karyotype is the number and appearance of chromosome in the nucleus of a eukaryotic cell The term is also used for the complete set of chromosomes in a species or in an individual organism and for a test that detects this complement or measures the number. 3

What are chromosomes? Humans. have 23 . pairs (2n=46) of chromosomes, with one chromosome from each parent. The chromosomes are coiled up DNA. Under normal conditions all of the chromosomes are inherited intact and in pairs. This is a normal karyotype of human chromosomes. A karyotype is a picture of chromosomes lined up to look at and compare Key Terms Genetic disorder Karyotype pedigree Causes of Genetic Disorders Genetic disorder - abnormal condition that a person inherits through genes or chromosomes Some are caused by mutations in the DNA of genes Others are caused by changes in the overall structure or number of chromosomes Cystic Fibrosis Body produces abnormally thick mucus. Times Arial Wingdings Apple LiGothic Medium Blueprint PowerPoint Presentation Chromosomal abnormalities Nondisjunction Alteration of chromosome number Nondisjunction Human chromosome disorders Down syndrome Down syndrome & age of mother Genetic testing Sex chromosomes abnormalities Klinefelter's syndrome Klinefelter's syndrome Jacob's. Human Karyotypes and Chromosomal Disorders The incidence of the syndrome is estimated as 1 in 3,000 live births. The incidence increases as the mother's age increases. - A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: 78bc83-Yjgy

Describe the causes and symptoms of 5 human genetic disorders. Causes pain and weakness. the human genome 14-1 human heredity 14-2 human chromosomes 14-3 human molecular genetics chromosomal disorders down syndrome trisomy 21 having 3 The PowerPoint PPT presentation: Human Genetic Disorders is the property of its rightful owner.. Human genes located close together on the same chromosome tend to be inherited together. Circle the letter of the characteristic of Down syndrome. b. mental - A free PowerPoint PPT presentation (displayed as a Flash slide show) on PowerShow.com - id: 25097e-ZDc1

PPT - Chromosomal abnormalities PowerPoint presentation

Chromosomal anomalies - SlideShar

Sex Chromosome Disorders: More common than autosomal disorders Turner syndrome (45, X) • 1:3000 female births • Extensive karyotype heterogeneity with question about existence of pure monosomy X (99% of 45, X eggs are non-viable) • Short stature, webbing of the neck, cardiovascular abnormalities, lack of secondary sex characteristics, strea An extra or missing chromosome is the main reason for the human genetic disorder. Chromosome abnormalities occur in 1 of 160 live human births (ref :- www.genome.gov) Figure 001 During meiosis when germ cells divide to create sperm and egg (gametes), each half should have the same number of chromosomes Human Chromosomal Abnormalities: Autosomal Abnormalities palomar.edu chromosomal abnormalities nethealthbook.com PPT - Common Chromosomal Abnormalities PowerPoint slideserve.co Chromosome disorders are of conditions, caused by constitutional numerical or structural abnormalities of chromosomes. Normally every cell of the human body has 46 chromosomes, organized in 23 pairs (22 pairs of autosomes, identical in males and females) and one pair of sex chromosomes - XX in females and XY in males

Abstract. The presence of numerical chromosome abnormalities in human embryos was studied using fluorescence in-situ hybridization with four or more chromosome-specific probes. When most cells of an embryo are analysed, this technique allows differentiation to be made between aneuploidy, mosaicism, haploidy and polyploidy Chromosomal abnormalities can also cause miscarriage, disease, or problems in growth or development. The most common type of chromosomal abnormality is known as aneuploidy, an abnormal chromosome number due to an extra or missing chromosome.Most people with aneuploidy have trisomy (three copies of a chromosome) instead of monosomy (single copy. Chromosomal Disorders 825147 PPT. Presentation Summary : Structural abnormalities. Rings: A portion of a chromosome has broken off and formed a circle or s can happen with or without loss of genetic material In some industrialised countries, pregnant women have non-invasive screening for Down's syndrome and other congenital anomalies through the assessment of maternal serum markers and ultrasonography at around 11 weeks post-conception. Recommendations: Screening should be done for every newborn using cord blood, or postnatal blood, ideally at 48 to 72 h of age. Some disorders can be detected.

PPT - The chromosomal and genetic abnormalities of cancer

Structural Abnormalities Deletions Translocations Inversions Duplications Deletions Loss of chromosomal material Large-scale deletions are lethal Example: Cri du chat Deletion of short arm of chromosome 5 Affects motor and mental function Infant cry resembles a meowing cat Specific chromosomal break points are associated with specific phenotypic changes Cri du chat Syndrome Structural. Teachers will assess what the students have learned about chromosomal abnormalities through the Chromosomal Abnormality Quiz taken in the Step 2. Additionally, the teacher will be assessing the PowerPoint presentations with the Chromosomal Abnormality PowerPoint Rubric included in Step 5

* * Figure 15.5 Human sex chromosomes. * * * * * Figure 15.7 The transmission of X-linked recessive traits. Scientific Inquiry PowerPoint Presentation Abnormal Chromosome Number Figure 15.13-1 Figure 15.13-2 Figure 15.13-3 PowerPoint Presentation PowerPoint Presentation PowerPoint Presentation Alterations of Chromosome Structure Figure 15. Title: PowerPoint Presentation Last modified by: mhalqahtani Document presentation format: On-screen Show Other titles: Times New Roman Arial Wingdings Comic Sans MS Verdana Network Microsoft Photo Editor 3.0 Photo Slide 1 Slide 2 Slide 3 Slide 4 Slide 5 Slide 6 Slide 7 Slide 8 Karyotyping Karyotype Preparing a karyotype Slide 12 Slide 13 Slide 14 The analysis involves comparing chromosomes.

Human Heredity Section 14-1 This section explains what scientists know about human chromosomes, as well as the inheritance of certain human traits and disorders. It also describes how scientists study the inheritance of human traits Several methods help map human chromosomes. A karyotype is a picture of all chromosomes in a cell. Human genetics follows the patterns seen in other organisms. The basic principles of genetics are the same in all sexually reproducing organisms. Inheritance of many human traits is complex. Single-gene traits are important in understanding human. Jacob's Syndrome 1 in 1,800 births 47 chromosomes XYY only 47XYY #23 Trisomy Nondisjunctio

Chromosomal Disorders in Humans. There are 46 chromosomes in each human cell present as 23 pairs (n pairs), out of which 22 are autosomes and 1 pair of sex chromosomes. Chromosomal disorders are caused because of the structural changes or numerical changes in chromosomes. A. Chromosomal Disorders Due to Numerical Abnormalities Translocation , ring chromosomes, inversions can present as balanced arrangements where the person is phenotypically normal. • Balanced rearrangements have an increased risk of history of infertility , multiple miscarriages or children affected with unbalanced structural or numerical chromosomal abnormalities and wit This is a normal karyotype of human chromosomes. A karyotype is a picture of chromosomes lined up to look at and compare. Add these terms to the back page of your SG21:Chromosomal Disorders. Chromosomal deletion: when cells go through meiosis, portions of the chromosome are lost

The Human Chromosomes . Every normal human cell, except for sperm and egg cells, has 23 pairs of chromosomes for a total of 46 chromosomes. Sperm and egg cells have only one of each pair of chromosomes for a total of 23. Each chromosome contains hundreds to thousands of genes. The sex chromosomes are one of the 23 pairs of chromosomes View Chromosomal disorders.ppt from BIO MISC at Kathmandu University. Chromosomal disorders APL 331 Dr Sudhamsu Koirala 1 • A chromosome has centomere, long arm (q) and short arm (p) • Eac Free Download Karyotypes and Chromosomal Disorders PowerPoint Presentation. Check out this medical presentation on Chromosome, which is titled Karyotypes & Chromosomal Disorders, to know about karyotypes and chromosomal disorders. Human Karyotype. Slide 6

unbalanced abnormalities, primarily deletion or loss of chromosome 5 or 7 (or both), whereas therapy with topoisomerase II inhibitors is typically associated with balanced abnormalities, most commonly translocations involving the MLL gene on chromo-some band 11q23.1 For most cancer-associated chromosomal abnormalities, how-ever, no specific. abnormalities of the central nervous system and eyes specifically at eight to 16 weeks after fertiliza-tion. Embryological timetables such as the one above are helpful in studying the etiology of human malformations. However, it is wrong to assume that malformations always result from a single even

Ch15 Chromosomal Abnormalities.ppt - Free download as Powerpoint Presentation (.ppt), PDF File (.pdf), Text File (.txt) or view presentation slides online. Scribd is the world's largest social reading and publishing site. Human chromosome disorders High frequency in humans 32. $22.00. $14.50. Bundle. Zip. BIG BUNDLE Genetic Disorders and DNA Mutations with Chromosomal Abnormalities is an excellent resource to use in a traditional, hybrid, or distance learning environment. The student guided notes and worksheets are in both printable and digital fillable pdf files

Chromosomal abnormalities characterized by an atypical number of chromosomes are called aneuploidy. For instance, trisomy 21 (Down syndrome) is caused by an extra copy of chromosome 21 in the egg or sperm that results in the fertilized egg receiving three copies of chromosome 21 The normal human karyotype is made of 46 chromosomes: 22 pairs of autosomes, numbered from 1 to 22 by order of decreasing length 1 pair of gonosomes, or sex chromosomes: XX in the female, XY in the male. Embryos with unbalanced constitutional anomalies have 1 or 3 copies of a whole set of genes, and abnormal development results. Note: a. The chromosomal abnormalities may occur either during the production of the egg or sperm or early after the baby's conception: a 2,3 spontaneous occurrence for unknown reasons . (1999)-Human.

One of the classic examples of the karyotyping abnormality is the down syndrome, a type of trisomy in which three copies of chromosome 21 are present. Usually human chromosomes appear in pairs but due to the event known as nondisjunction sometimes an extra chromosome also appears with a pair. That exactly happens with down syndrome Often happens to 2 chromosomes at once! • Both nondisjunction and translocation can be detected in _____ o Made from taking individual pictures of all of a human's chromosomes and matching up _____ A) Down syndrome - a genetic disorder that results from chromosome abnormality

PPT - Chromosome Abnormalities PowerPoint presentation

Many human genetic disorders result from unbalanced chromosome abnormalities, in which there is a net gain or loss of genetic material. Numeric and structural chromosomal abnormalities occur in approximately 0.6% of live births,1 and often result in dysmorphism, malformations, and/or developmental disabilities. The resulting phenotypes are. The National Institute of General Medical Sciences (NIGMS) Human Genetic Cell Repository was established in 1972 to provide a readily accessible, centralized resource for genetic material from individuals with inherited defects in metabolism, chromosomal abnormalities, and other genetic disorders. This biobank creates cell lines, DNA and other. Human Genetics: Chromosomal Aberrations See online here Chromosomal aberrations are chromosome mutations that entail changes in the genome. These changes can affect either part of a chromosome or an entire In contrast to the abnormal distribution of gonosomes, the aneuploidy of autosomes results in distinct mental and physical impairment Chromosome anomalies are extraordinarily common in human gametes, with approximately 21% of oocytes and 9% of spermatozoa abnormal. The types of abnormalities are quite different since most abnormal oocytes are aneuploid, whereas the majority of abnormalities in spermatozoa are structural. Chromosomes 21 and 22 (the smallest chromosomes) are over

Chromosomal Abnormalities PPT and PDF Free To Downloa

  1. Others are caused by chromosomal mutations. Some human genetic disorders are X-linked or Y-linked, which means the faulty gene is carried on these sex chromosomes. Other genetic disorders are carried on one of the other 22 pairs of chromosomes; these chromosomes are known as autosomes or autosomal (non-sex) chromosomes. Some genetic disorders.
  2. Chromosomes that are paired together because they are similar in size, shape, and the genes they carry are called _____ Chromosomal abnormalities DRAFT 9th grad
  3. G-banded Human Karyotype Tjio & Levan 1956 Karyotype: The characterization of the chromosomal complement of an individual's cell, including number, form, and size of the chromosomes. A photomicrograph of chromosomes arranged according to a standard classification
PPT - Genetics & Heredity PowerPoint Presentation, freeHuman Inheritance & Genetic Disorders

Human Karyotype ( Chromosomes) - SlideShar

Julie A. Gainer, in Obstetric Imaging: Fetal Diagnosis and Care (Second Edition), 2018 Introduction. Chromosome abnormalities are often the cause of early pregnancy loss, fetal malformations, and stillbirth. Triploidy is a lethal chromosome abnormality caused by the presence of a complete extra set of chromosomes (Fig. 148.1); it can lead to spontaneous miscarriage, congenital anomalies. Fig. 3.1 G-banded normal male karyotype illustrating the characteristic size, centromere position, and G-banding banding pattern for each human chromosome pair Chromosome Banding and Identification Launched in the early 1970s, banding methods allow for the identification of chromosomes not only by length and centromere position, but also by their unique banding properties Chromosomal abnormalities can cause serious mental or physical disabilities. Down syndrome, for instance, is caused by an extra chromosome 21 (trisomy 21). People with Down syndrome are usually mentally retarded and have a host of physical defects, including heart disorders

Chromosomal abnormalities, alterations and aberrations are at the root of many inherited diseases and traits. Chromosomal abnormalities often give rise to birth defects and congenital conditions. Problem 4 Easy Difficulty. Comparatively few human genetic disorders are caused by chromosomal abnormalities. One reason is that. a. most chromosomal abnormalities have little effect. b. it is difficult to detect changes in the number or length of chromosomes. c. most chromosomal abnormalities result in spontaneous abortion of the embryo 2.4: Chromosomal Abnormalities. A chromosomal abnormality occurs when a child inherits too many or two few chromosomes. The most common cause of chromosomal abnormalities is the age of the mother. As the mother ages, the ovum is more likely to suffer abnormalities due to longer term exposure to environmental factors

PPT - Human Karyotypes and Chromosomal Disorders

Family Practitioner. There are many types of chromosomal disorders. The most common is Down syndrome, which is most often caused by an extra copy of chromosome 21. Fragile X is a disorder that has DNA abnormalities on the X chromosome. In boys, the abnormality is most often inherited from their mother. Kleinefelter's syndrome occurs when boys. @article{osti_5675602, title = {Chromosomal abnormalities in human sperm}, author = {Martin, R H}, abstractNote = {The ability to analyze human sperm chromosome complements after penetration of zona pellucida-free hamster eggs provides the first opportunity to study the frequency and type of chromosomal abnormalities in human gametes. Two large-scale studies have provided information on normal. Chromosomal aberrations including structural variations (SVs) are a major cause of human genetic diseases. Their detection in clinical routine still relies on standard cytogenetics. Drawbacks of these tests are a very low resolution (karyotyping) and the inability to detect balanced SVs or indicate the genomic localization and orientation of duplicated segments or insertions (copy number. <p>Chromosomal abnormalities are common causes of birth defects that can affect the brain and other parts of the body. The normal fertilized egg cell contains 23 chromosomes from the mother and 23 from the father. Thus, there are normally 23 pairs of chromosomes in the fertilized egg. These include two sex chromosomes: XX for girls and XY for boys Results from the NCI study showed that risk of leukemia was also substantially higher among people with these chromosomal alterations while the GENEVA study showed that the risk of acquiring a hematological cancer diagnosis was 10 times higher for people who had mosaic chromosomal abnormalities

Spontaneous abortion occurs in 15-20% of clinically recognized gestations [].Genetic defects, especially chromosomal abnormalities, are the most common cause of spontaneous miscarriage during the first trimester; indeed, chromosomal abnormalities occur in approximately 60% of such cases [].It is unclear whether pregnancies conceived through assisted reproductive treatment (ART) are at an. Chromosomal abnormalities. The distribution of chromosomal abnormalities in murine leukemias arising in PML-RARA (A, 11 cases) orPML-RARA/BCL2 (B, 8 cases) mice reveals a defined spectrum of numerical abnormalities. Chromosome gain is depicted by green bars on the right of each chromosome, and chromosome loss is depicted by pink bars on the left Chromosomal Abnormalities. Nondisjunction: failure of homologous chromosomes in germ cells to separate in first or second meiotic division. May involve either sex chromosomes or autosomes. Causes abnormalities in distribution of chromosomes between germ cells. One of two germ cells has an extra chromosome while the other lacks a chromosom

PPT - Human Genetic Disorders PowerPoint presentation

  1. Basics of Genetic disorders. Single-gene disorders, where a mutation affects one gene. Chromosomal disorders, where chromosomes (or parts of chromosomes) are missing or changed. Complex disorders, where there are mutations in two or more genes
  2. Nondisjunction may result in gametes with an abnormal number of chromosomes, which can lead to a disorder of chromosome numbers. Chromosomal Disorders If two copies of an autosomal chromosome fail to separate during meiosis, an individual may be born with three copies of that chromosome
  3. Autosomal and sex-linked genetic disorders are both caused by certain alleles - small segments of DNA that make up part of a chromosome. Other genetic disorders result from chromosome abnormalities caused by mistakes made during meiosis. May change the number or structure of chromosomes within gametes. Chromosome Abnormalities

PPT - Human Chromosomes Section 14 PowerPoint presentation

  1. Joe Mary Pete Isabel Ww ww Ww ww WW A karyotype is a picture of all chromosomes in a cell. X Y Karyotypes can show changes in chromosomes. deletion of part of a chromosome or loss of a chromosome large changes in chromosomes extra chromosomes or duplication of part of a chromosome In down syndrome a person has an extra copy of chromosome 21
  2. Congenital Malformation: A condition that is present at birth. Multi-factorial Defects: Interaction of genes with other genes OR with environmental factors. Chromosomal Error: The fertilized egg cell that contains chromosomes in an abnormal number, structure or arrangement

Chromosomal Disorders in Humans: Structural changes

Numerical and Structural Abnormalities Of Chromosomes Chromosomal abnormalities or aberration is a missing , extra or irregular portion of chromosomal DNA . They usually occur as a result of errors in meiotic / mitotic cell division. They can be inherited from a parent or be de novo BIG BUNDLE Genetic Disorders and DNA Mutations with Chromosomal Abnormalities is an excellent resource to use in a traditional, hybrid, or distance learning environment. This is a Powerpoint presentation on Genetics, Human Heredity and Pedigrees and concepts dealing with Monohybrid, Dihybrid Crosses, and Tracking Genetics through Pedigrees..

Chromosomal anomaliesPPT - Genes, Chromosomes, and Human Genetics PowerPoint

(PPT) Human genetic Disorders Arnold Ashley - Academia

Other chromosomal abnormalities such as trisomy 13 and trisomy 18 also had a large proportion of fetal deaths or terminations of pregnancy and were more common in women aged 40 years or older. Neural tube defects were diagnosed in about 4.2 per 10,000 births The Lancet LEADING ARTICLES Human Chromosomal Abnormalities Many of those who attended the first symposium on Nuclear Sex at King's College Hospital, London, two years ago met there again last week with some new colleagues to discuss human chromosomal abnormalities. The two subjects might at first seem not very closely related; but the number.

Human Chromosomal Abnormalities Autosomal Abnormalitie

Related Internet Sites. Links to General Information Concerning Chromosomal Abnormalities and Prenatal Testing: Chromosome Abnormalities (summary of the important facts about chromosome abnormalities; National Human Genome Research Institute of the National Institute of Health); Chromosome D isorder Outreach (An International Support Group for Families Affected b Human genetic disease - Human genetic disease - Abnormalities of the sex chromosomes: About 1 in 400 male and 1 in 650 female live births demonstrate some form of sex chromosome abnormality, although the symptoms of these conditions are generally much less severe than are those associated with autosomal abnormalities. Turner syndrome is a condition of females who, in the classic form, carry. Chromosomal rearrangements constituted 27.78% of the cases while heterochromatic chromosomal cause for recurrent miscarriages. In the present study, pericentric inversion of chromosome 9 and heteromorphism of ariants as these variants play an important role in pregnancy loss. Keywords Chromosomes, Heteromorphisms, Karyotype

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Introduction to Chromosomes - Chromosome Disorder Outreach In

Human chorionic gonadotropin (hCG) will assist in making the diagnosis. Partial mole - three sets of chromosomes instead of the usual two and this is called triploidy. With such a pregnancy the chromosomal (genetic) material from the ovum (egg) is retained and the egg is fertilized by one or two sperm Abnormalities in Human Development. This means that they are genetic disorders. A genetic disorder is a condition caused by a defective gene or other chromosomal abnormality Human genetic disorder occurs due to abnormalities of individuals of genetic materials. Human genetic disorders are of different types depending on the causes. There are four types of genetic disorders; single-gene, chromosomal, multifactorial and mitochondrial. Genetic disorders are mainly caused by mutation of genes and DNA The 23rd pair consists of 2 sex chromosomes (gonosomes) X and Y, resulting in a complete set of 46 chromosomes in a human somatic cell. Overall, the numerical chromosomal aberrations are genome mutations, which are attributed to the faulty distribution of chromosomes among the daughter cells Crossword Puzzle Solution for Human Chromosomal Abnormalities . Copyright © 2005 by Dennis O'Neil.All rights reserved

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ADVERTISEMENTS: In this article we will discuss about the classification of human chromosomes on the basis of size and position of the centromere. All the human chromosomes in nor­mal numbers (46) can be arranged in groups based on size and positions of the centromere. The resulting classification of the chromo­somes is given in the following [ Advanced maternal age increases the risk of chromosomal abnormalities, including Down syndrome. Environmental factors Maternal exposure to certain pesticides and other chemicals, as well as certain medications, alcohol, tobacco and radiation during pregnancy, may increase the risk of having a fetus or neonate affected by congenital anomalies The sex chromosomes determine whether a fetus becomes male or female. A pair of X and Y chromosomes (XY) results in a male, and a pair of X and X chromosomes (XX) results in a female. Sex chromosome abnormalities occur when a person is missing a whole sex chromosome (called monosomy) or has an extra sex chromosome (one extra is trisomy)