Loading....
Coupon Accepted Successfully!

 

Sex Determination

A. By Sex Chromatin

B. By Bones


1.
Sex Chromatin
 
Sex from chromatin can be determined by following methods.
  1. Barr body: it’s a small planoconvex mass lying near nuclear membrane. Seen in Buccal smear, saliva and hair follicle of females in 20-80% of cells. In males, seen in 0-4% of cells.
  2. Davidson smith body: Drumstick form of nuclear appendage in neutrophil of females (6% of cells). Absent in males.
  3. Feulgen reaction: AcriFlavin schiff reagent used to stain X chromosome which is seen as bright yellow spot.
  4. Quinacrine staining: Y chrom. Demonstrates fluoroscence when stained with Quinacrine dihydrochloride.

 2.  Sex from skeletal remains
 

   BONES

MALES

FEMALES

SKULL

Glabella, supraorbital ridge, cheek bones, occipital area, mastoid process, palate, foramina, foramen magnum and teeth: all are prominent or large or more marked.

 

Frontal eminence: small *

Parietal eminence: small

 

Orbit : square, smaller

All these are less prominent or smaller or less marked.

 

 

 

 

 

Large *

Large

 

Orbits: Rounded, larger

MANDIBLE

General size, ramus and condyles are larger.

 

Angle of body and ramus: Less obtuse ( < 125o), prominent, everted

 

Chin : Square *

Smaller

 

 

More obtuse, not prominent, inverted

 

 

Chin: Rounded *

 

3. Sex from skeletal remains

 

MALES

FEMALES

  PELVIS

 

SHAPE:

 

PREAURICULAR             SULCUS *:

 

GREATER* SCIATIC NOTCH

 

Sub pubic angle:

 

 

Obturator foramen:

 

 

ISCHIOPUBIC INDEX:

Pubic length in mm  X 100

Ischial length in mm

 

 

SCIATIC NOTCH INDEX:

Width of sciatic notch X 100

Depth of sciatic notch

 

CORPOBASAL INDEX OF SACRUM: (breadth of 1st sacral vertebrae/ Breadth of base of sacrum X 100)

 

Massive, rough, marked muscle sites

Deep funnel

 

Not frequent, narrow, shallow


Smaller, narrower, deeper

 

‘V’ shape, 70-750

 

 

Large, OVAL* , with base upwards

 

 

   73 – 94 in males

 

 

 

 

     4-5

 

 

 

- More in males (45)*

 

Less massive, smoother

 

Flat bowl

 

Frequent, broad, deep

 

 

Larger, wider, shallower

 

 

‘u’ shape, 75-900, broad

 

 

Small, triangular, with apex forwards

 

 

 

91 – 115 in females

 

 

 

 

5 – 6 in females

 

 

 

Less in females(40)

 

    

4. Sex from skeletal remains

Sternum

 

 


Sternal index:

length of manubrium X 100  length of body

 

Ashley’s rule * :

Body longer and more then twice the length of the manubrium.

 

46.2

 

 

length > 149mm

-Body shorter and less then twice the length of the manubrium.

 

  54.3 in females

     

 

  < 149mm

 
5.
KROGMAN’S TABLE

According to KrogMAN, the degree of accuracy in sexing * by the examination of bones is:

Entire skeleton - 100%
Pelvis + skull - 98%
Pelvis - 95%
Skull - 90%
Long bones alone - 80%
 

Extra Edges

  1. Best bone for determination of sex is PELVIS.
  2. Best criteria in pelvis for sex determination is SCIATIC NOTCH INDEX.
  3. CORPORO-BASAL INDEX is more in males.





Test Your Skills Now!
Take a Quiz now
Reviewer Name