Types of human genetic disorder

important terms:

aneupliody:its the condition in which a cell has  more or fewer number of chromosomes than the normal diploid number (46)

types of aneuploidy

1.hyperploidy

its a type of aneuploidy where the  total number of chromosomes is greater than normal. for eg. down syndrome(47),klinefelter syndrome(47),edward syndrome(47).

2.hypoploidy:

its a type of aneuploidy where the total number of chromosomes is less than normal for eg.turner syndrome (45)

causes of aneuploidy:

during the cell division of anaphase stage there is a non dis junction  and chromosome are fail to seprate properly .

types of human genetic disorder 

there are two types of genetic disorder 1. mendelian disorder   2. chromosomal disorder .

1.mendelian disorder:   

its determine by mutation of single gene .

this disease also known as gene related disorder 

they are transmitted to offspring as per mendelian principal 

can be studied through pedigree analysis

2.chromosomal disorder:

disorder created due to imbalance in number of chromosomes 

can be studied through pedigree analysis.

mendelian disorder disease

.there are two types of mendelian disorder 

1.autosomal disorder :

for eg. sickle cell anemia, phenylkutoneria,thalassemia,cysticfibrosis,albenism, myotonic dystrophic.

2. sex linked disorder:

for eg , colour blindness ,heamophillia,mascular dystrophy.

1.phenylketonuria

its a type of autosomal recessive disorder  when gene produces enzyme phenylanaline hydroxylase  which is convert phenylanaline to tyrosine buttt

in mutated gene no enzyme are produce so phenylanaline are convert into phenyl pyruvic acid  hence they are accumalation in brain  as result is mental retardation   

. excereted in urine due to poor absorbtion in kidney 

 . affected gene is brain cell affect,skin pigmantation 

2.sickle cell anemia :

its a type of autosomal rescessive disorder . associated with chromosome number 11 

 its due to when glutamic acid is replaced to valine 

 its a type of qualitative disorder.

 .sickle cell blocking the blood flow 

3. thalassemia:

its type of autosomal recessive disorder 

transmitted offspring when both perents are carrier 

types of thalassemia:

1 alpha thalassemia:

.at chromosome number 16.

. affected gene is HBA1 HBA2 .

. reduced synthesis od alpha chain. hence beta precipitate and RBC are ruptured .

2. beta thalassemia:

. at chromosome number 11 
affected gene are HBB 

reduced synthesis of beta chain and alpha precipitate . hence RBC are ruptured .

sex linked disorder:

1 .colour blindness :

its a type of sex linked recessive disorder 

. in this type of disease person can inability to find the diffrenciate between red and green colour .its due to  mutation of genes present on X chromosomes  

ocour in male 8% an in female 0.4%

2. heamophillia:

its a type of sex linked recessive disorder 

single protain that are involve in caseade of protein involve  blood clotting is affected 

in this type of disorder small cut can affected uncantrolled bleeding 

 queen victoria was the first carrier of this disease hence also called (ROYAL DISEASE).

 

 chromosomal disorder

1. down syndrome:

.its a type of autosomal  hyperploidy  disorder 

.prensence of addition of chromosomes number 21 show trisomy .

.occour in both male and female .total number of chromosomes becomes 47 

features :

. short saturated small round head 

.broad flat face, eye fold are absent, partially open mouth ,farrowed and wrinkled tounge ,cogenital heart disease,palm broad with palm crease,many loops on finger tips,mental development are retarded , under developed gonad and genital area.

2.klinefelter syndrome :

.discovered by klinefelter.

.sex linked hyperploidy disorder.

.presense of addition of one copy of X chromosomes.

.sex affecter- male.

.total number of chromosomes becomes 47

.in male feminine character are developed such as breast development ,overall masculine development .

.they become lifetime infertile [sterile]

features:

.tall stature,breast development,poor beard growth,wide hips, small size testies ,poor muscle tone, reduce secondary sexual character . XXY extra  x chromosomes  are add between x and y

3.turner syndrome:

.its a type of sex linked anuploidy disorder .

. loss of 1 copy of X chromosomes( 2n-1)

features:

.short stature,mostly in female,ovary and genital are rediment ,no mensuration ,poor breast development ,lack of other secondary sexual character, webbed neck .(44+XO)